Issued Scplombor 17, 1911. 

PORTO RICO AGRICULTURAL EXPERIMENT STATION, 

D. W. MAY, Special Agent in Charge, 

C cqo Mayaguez, P. R. 

.G56 



'^''Py ^ - Bulletin No. 16. 



THE EFFECT OF STRONGLY CALCAREOUS SOILS 
ON THE GROWTH AND ASH COMPOSI- 
TION OF CERTAIN PLANTS. 



p. L. (IILE, 

Chemist, 



AND 



C. N. AGETON, 

Assistant Chemist. 



UNDER THE SUPERVISION OF 

OFFICK OF EXPERIMENT STATIONS. 

U. 3. DEPARTMENT OF AGRICULTURE. 



W.A.SHTNGTON: 

OOVKRNMENT PRINTING OFFTOE. 

1914. 



MtfiMgrapli 



Issued September IT, I'.iH. 

PORTO RICO AGRICULTURAL EXPERIMENT STATION, 

D. W. MAY, Special Agent in Charge, 

Mayagucz, P. R. 



Bulletin No. 16. 



THE EFFECT OF STRONGLY CALCAREOUS SOILS 
ON THE GROWTH AND ASH COMPOSI- 
TION OF CERTAIN PLANTS. 



p. L. GILE, 

Chemist, 



C. N. AGETON, 

Assistmit Chemist. 



UNT>ER THE SUPERVISION OF 

OTTICE OF EXPERIMENT STATIONS, 

U. S. DEPARTMENT OF AGRICULTURE. 



WASHINGTON: 

GOVERNMENT PRINTING OFFICE. 

1914. 






PORTO KICO AGRICULTUEAL EXPERIMENT STATION. 

[Under the supervision of A. C. True, Director of the OiTice of Experiment Stations, United States 
Department of Agriculture.] 

Walter H. Evans, Chief of Diiision of Insular Stations, Office of Experiment Stations. 

STATION STAFF. 

D. W. May, Special Agent in. Charge. 

P. L. GiLE, Chemist. 

G. L. Fawcett, Plant Pathologist. 

C. F. Kinman, Horticulturist. 

R. H. Van Zwaluwenburg, Entomologist. 

T. B. McClelland, Assistant Horticulturist. 

C. N. Ageton, Assistant Chemist. 

W. E. He.ss, Expert Gardener. 

C. Alemar, Jr., (7(T^-. 

(2) 

OCT 3 m4 



c 



iriTRR OF TRANSMITTAL. 



Porto Rico Agriculturai. Experiment Station, 

Mayaguez, P. R., Ffhruary 13, 1914. 
Sir: I have the honor to transmit herewith a manuscript hy P. L. 
Gile and C. N. Ageton on The Effect of Strongly Calcareous .Soils on 
the Growth and Ash Composition of Certain Plants. In plant pro- 
duction we have tried and measured arid weighed many results 
obtained bj^ methods more or less uncertain and inexact. It is 
becoming increasingly evident that we must go farther back and 
seek for principles in order that our efforts may lead to more exact 
and concordant returns. This bulletin throws some light on the 
relation of certain elements in plant growth and will prove of value 
in further researches. 

I recommend that tliis manuscript be published as Bidletin Ifi of 
this station. 

Respect fullv, 

D. W. May, 
Special Agent in Charge. 
Dr. A. C. True, 

Director Office of Experiment Station/^, 

U. S. Department of AgricvJtiire, Washington, D. C. 

Recommended for publicaticni. : • 

A. C. True, Director. "^ , 

Pubhcation authorized. 
D. F. Houston, 

Secretary of Agriculture. 
(3) 



CO NTH NTS. 



Page. 

Introduction 7 

PrevioiKs work 7 

On the influence of carbonate of lime on the growth of plants 7 

On the influence of carbonate of lime on the ash composition of plants 8 

Plan of the investigation 12 

Materials and methods employed ll! 

Growth and composition of various plants on the calcareous and noncalcareous 

soils 15 

Bush beans 15 

Soy beans 18 

Sunflowers 19 

Radishes 22 

Sugar cane 25 

Sweet cassava 26 

Upland rice 29 

General summary of experimental results 33 

The effect of carbonate of lime on the growth of plants 33 

The effect of carbonate of lime on the ash composition of plants 34 

The effect on growth compared with the effect on ash composition 37 

Discussion of results 38 

Summary 44 



ILLUSTRATIONS. 



Page. 

Plate I. Arrangement of plats on which plants were grown 12 

II. Fig. 1. — Sweet cassava grown with no lime, Plat I. Fig. 2, — Sweet 

cassava grown with 5 per cent lime, Plat II 12 

III. Fig. 1. — Sweet cassava grown with 18 per cent lime, Plat III. Fig. 

2. — Sweet cassava grown with 35 per cent lime. Plat IV 21 

IV. Fig. 1. — Rice grown without lime. Plat I. Fig. 2. — Rice grown with 
5 per cent lime, Plat II. Fig. 3. — Rice grown with 18 per cent lime, 
Plat III. Fig. 4. — Rice grown with 35 per cent lime, Plat IV. ... 24 

(5) 



THE EFFECT OF STRONGLY CALCAREOUS SOILS ON 
THE GROWTH AND ASH COMPOSITION OF CER- 
TAIN PLANTS. 



INTKODXTCTION. 

Many soil troubles in Porto Rico !i])pcar to bo duo to an excess of 
liiuo or to the acidity attending a deficiency of lime. In a previous 
bulletin of tliis station ' attention was called to tbe action of an 
excess of lime in rendering soils unsuitable for the cidtivation of ])ino- 
ajjples. Besides pineapples, some other cro]:)s refxise to grow on the 
excessively ciilcareous soUs, or else give evidence of nutritional dis- 
turbances by tiie chlorotic appearance of their leaves. Since a con- 
siderable portion of the arable land of P(u-to Kico is moderately or 
excessively calcareous it is believed that uivestigations to detcrmme 
the cause and ciu'e of these disturbances are important. As a part 
of such Liivest.igations, a study has been made of the effect of varying 
amounts of carbonate of lime in tlie soil u])on the growth and mineral 
com])osition of various plants. 

Since the nutritional disturbances of some ))lants on the excessively 

calcareous soils are evidently caused by the chemical and not tlie 

physical character of these soils, it was thoiight that a comparison 

of tlie ash contents of plants grown on a normal and on a calcareous 

soil might indicate the nature of the disturbance. The data reported 

throw some light on this specific problem as well as on the more 

general subject of the effect of the soil on the ash compositionof 

))lants. 

PREVIOUS WORK. 

ON TUE INFLUENCE OF C'AKBONAJE OF LIME ON THE GROWTH OF 
PLANTS. 

Tliere are few quantitative data on the effect of strongly calcareous 
soils on the growth of jilants. The residts of orduiary liming experi- 
ments, which show the effect of alterations in the soil reaction, do 
not apply to this hivcstigation, except that plants thriving best on 
acid soils must be expected to show a depression on strongly cal- 
<'areous soils.' 

1 Porto R ico Sta. Bui. U. 

» Whcclcr, H. J., ct al., Rhode Island Sta. Rpts. 1S93, pp. 224-252; 1894, p. 152; 1895, p. 205; 1896, p. 242: 
1S97, p. 202; 1S9S, p. 144; 1S99, p. 171; 1900, p. 293. Coville, F. V., U. S. Dept. Agr., Bar. Plant Indo-s. 
Bui. 193; U. S. Dept. Agr. Bui. 6. 

(7) 



Tliere is, however, an exteii.sive literature on calcipliilous and 
calcifxigoiis plants, whicli for the most part consists of observations 
on the occurrence or nonoccurrence of plants on calcareous soils.' 
Tliesc studies, wliich have afforded rather conflicting results, seem to 
show that there are a very few plants which never occur naturally 
on calcareous soils, but the observations do not show with certainty 
whether this is due to the physical or chemical character of the soils. 
There are also some cidtin-e experiments which show that some plants, 
as certain varieties of lupmes,- sphagnum moss,^ serradella,* pine- 
apples,^ etc., are intolerant of calcareous soils. 

Tlie many studies on the chlorosis of fruit trees and graj^evines 
show that many calcareous soils are not adapted for certaiii trees 
and vines. A partial review of the literature on lime-induced chlorosis 
is given in the bulletin of this station referred to above. 

On the whole the literature shows that some j>lants are extremely 
intolerant of much carbonate of lime in the soil, some are indifferent, 
antl others recjuire considerable carbonate of lime to make their 
maximum growth. 

ON THE INFLUENCE OF CARBONATE OF LIME ON THE ASH COMPOSITION 
OF PLANTS. 

No comprehensive studies have been made to determine whether 
the mineral composition of different plants is affected m any con- 
stant mamier by large amounts of cai'bonate of lime in the soil, but 
some work has been done along tliis line. 

Fliche and Grandeau analyzed the ash of the maritime ]>ine {Pinus 
pinaster), tlie chestnut (Casfanea vesca), and the bean tree {Cytisus 
laburnum), from calcareous and noncalcareous soils. The calcareous 
soil contained 3.25 per cent of lime in the surface soil and 24.05 per 
cent in the subsoil, while the siliceous or noncalcareous soil contained 
0.35 per cent of lime in the surface soil and 0.20 per cent in the sub- 
soil. Tlie bean tree grew equally well on the two classes of soU, 
while the chestnut and maritime ])ine grew well on the siliceous soil, 
but developed very poorly, sliowing strong chlorosis, on the calcareous 
soil. Analyses, by Fliche and Grandeau," of samples from trees of 

> Hilgard, E. W., Soils, New York and Lomlon, 1906; Proc. Soc. Prom. Agr. Sci., 7 (1S86), p. 32. Hoaman, 
H., Landw. Vers. Stat., 13 (1871), p. 269. Braungart, R ., Jour. Landw., 28 (1880), p. 155. Roirx, J. A. C, 
Traite dcs Rapports des Plantes avec le sol et de la Chlorose V(%tHale, Paris, 1900. Kraas, G., Boden und 
KlimaautkleinstemRauin, Jena, 1911. Vogler, P., Ber. Schweiz. Bot. GeseU., 1901, No, 11, p. 63. Engler, 
A., idem, p. 23. Schimper, A. F. W., Pflanzen-geographie auf Physiologischer Grundlage, Jena, 1898. 

sHeinrich, R., Mergel und Mergeln, Berlin, 1896. Pfeiffer, T., and Blanek, E., Mitt. Landw. Inst. 
Breslau, 6 (1911), No. 2, p. 273. 

» Paul, H., Ber. Deut. Bot. GeseU.. 21 (1906), p. 148. 

* Meyer, D. Die Kalk und Magnesiadungiing, Berlin, 1910, p. 61. 

sGile, P. L., Porto RicoSta. Bui. 11. 

9 Fliche, P., and Grandeau, L., Ann. Chun, et Phys., 4.ser., 29 (1873). p. 383; 5. ser., 2 (1874), p. 354; 5 
ser.. 18(1879), p. 268. 



the sa.mo aj^e, gruwai on tlie talc-areoiis and noncalcareous soils, are 
given in Tabic I. 

Table I. — Ash analyses by FIlclic and Grandcau of trees from calcareous an/1 siliceous soils. 









Maritime pine — 




Chestnut. 


Bean tree — 




branches. 


T-eaves. 


Wood. 


branches. 




Siliceous 
soil. 


Calcare- 
ous soil. 


Siliceous 
soil. 


Calcare- 
ous soil. 


Siliceous 
soil. 


Calcare- 
ous soil. 


Siliceous 
soil. 


Calcare- 
ous soil. 


Ash 
Pho 


in drv m 
sphorica 
(Fe.o,! 

((':,! I|- 


:ltlOr 

-icKP.Os).. 


Per cent. 
1.32 
9.00 
3. Si 
■10.20 
20.09 
16.04 
1.01 

',1. 1 S 


Per cent. 
1.54 
9.14 
2.07 
56.14 
IS. .SO 
4.n.i 
2.52 

""6.'42" 


Per cent. 
4. so 

12.32 
1.07 

45.37 
6.63 

21.67 
3.86 
2.97 
.5.7!) 
.30 


Percent. 
7. .SO 
12.50 
.83 
74. 55 
3.70 
5.76 
.66 
.00 
1.46 


Per cent. 
4.74 
4.53 
2.04 

73. 26 
3.99 

11.65 
.00 
1.43 
3. 0,S 


Percent. 
5.71 
4.27 
1.27 

87. 30 

2. m 

.2S 
.64 
1.36 
.08 


Per cent. 
1.19 
16.74 

3. 05 
27. l.i 
17.76 
23.77 

3.05 

4. .52 
3.96 


Per cent. 
1.39 
11.57 


T in 








idVso,]'.'.: 








24.50 
12.68 
3.73 


rtilf 


rin (Clj) 























They concluded that the maritime ]iiiic and chestnut on the cal- 
careous soils absorbed an undue amount of lime, which caused a dim- 
inution m the other elements, notably in potash and iron; the increase 
in lime and diminution in potash and iron caused the poor growth of 
these trees on the calcareous soils. They further state that tlie 
presence of an excess of hme in the soil appears to be always un- 
favorable to the absorption of iron. It will be noticed that the bean 
tree, which grew equally well on the two soils, showed practically the 
same content of lime, potash, and iron in the ash when grown on the 
calcareous as when grown on the siliceous soil. 

Wolff reports analyses by ZoUer, Kochlin, and Rothe of barley 
seeds, madder roots, and bugle weed from low-Ume and calcareous 
soils.' Unfortunately the comparative growths of the plants on 
the two classes of soil are not given, so the results are not particularly 
illuminating for our purpose. Nor is it e\ndent that the comparative 
samples of plants were grown under like climatic concUtions. The 
barley seeds were grown on soils containing 1.55 per cent and 23.04 
per cent of CaCOj, but there was no difference in the ash content 
and ash composition of the seeds from the two soils. The madder 
roots from the calcareous soils contained one-third as much FejOg, 
CI2, and SiOj and one-half more SO3 than the roots from the low- 
lime soil. The bugle weed (Ajuga reptans) was grown on soils con- 
taining 0.14 per cent of CaO and 37.16 per cent of CaCOg. The 
plants grown on the calcareous soil differed from those grown on 
the low-Ume soil in containing twice as much magnesia and chlorin, 
one-third as much silica, and one-fourth as much soda. 

1 Wolfl, E. Aschen-analysen. Berlin, 1.871, pp. IS, 116, 138. 



10 

Malaguti and Durocher ' determined the lime in the ash of a number 
of wild plants growing on calcareous and noncalcerous soils and 
obtained the results given in Table II. 

Table II. — Analyses by Malaguti and Durocher of wild plants from calcareous and 
noncalcoreous soils. 



Kind of plints. 



Cruciferw (6 analyses) 

Lep:iiminos3R (6analyses)... 

Dipsacacejf (5 analyses) 

Saiicacc.T , Populus"f5 analy; 

Average 



Per cent. 
35.79 
■SO. 26 
.3S. 65 



Per cent. 
20.12 
28.12 
20.63 
51.16 



.30.01 



Li five species of plants the lime, soda, and potash m the ash were 
also determined, as shown m Table III. 

Table III. — Analyses by Malaguti and Durocher of wild plants from calcareou.'! and 
noncalcareous soils. 





CaO in ash of plants 
grown on — 


KoO in ash of plants 
grown on- 


Na20 in ash of plants 
grown on- 


Species of plant. 


Cal- 
careous 
soil. 


Non- 
calcare- 
ous soil. 


Cal- 
careous 
soil. 


Non- 
calcare- 
ous soil. 


Cal- 
careous 
soil. 


Non- 
calcare- 
ous soil. 




Per cent. 
27.98 
43.60 
43.32 
36.18 
28.60 
22.61 
6.24 
70.14 


Per cent. 
13.62 
19.48 
29.72 
26.68 
17.16 
11.41 
4.62 
54.00 


Per cent. 


Per cent. 


Per cent. 


Per cent. 




12.34 
9.60 
19.11 


25.42 
27.20 
28.74 


5.56 
4.80 
13.80 


















40.23 


42.44 


2.26 










11.60 


19.83 


2.18 










34.83 


22.09 





















RotJie ^ has analyzed the rupture-wort {Herniana glabr'a) from a 
sihca sand and dolomite sand. The dolomite sand contained about 
56 per cent CaCOj and 43 per cent MgCOj. The silica sand was made 
up of quartz and feldspar. The plants from the two soils contained 
about the same amount of crude ash, but the ash of the plant from 
the dolomite sand differed from the ash of the check plant in con- 
taining oue-tliird as much potash, twice as much Hme, three-fifths as 
much iron, tliree times as much magnesia, one-twelfth as much silica, 
and one-seventh as much potassium clilorid. The two samples were 
taken from chfferent locahties and it is not stated whether the plants 
were of the same age or not. 



I Malaguti and Durocher, Ami. Sei. Nat. Bot., 4. ser., 9 (1858), p. 222. 
» Rothe, C, Ber. Naturhist. Ver. Augsburg, 1869, p. 145. 



11 

Some results secured by Ilasellioff ' in studying the decomposition 
of certain rocks are interesting in this connection. Peas, beans, 
lupines, barley, and wheat were grown in rocks powdered to a fineness 
of 5 to 0.5 millimeter. Two of the rocks used were sandstone (Bunt- 
sandstein) and limestone (Musclielkalk). The sandstone contained 
no carbonate of Ume and the Hmestone about 94 per cent. Barley 
and wheat, which made almost no growth on any of the rocks, con- 
tained no more lime when grown on the Hmestone than when grown 
on tlie sandstone. Peas, beans, and lu])ines, which made a relatively 
good growth on the sandstone and a greatly diminished growth on the 
limestone, contained respectively two, five, and three times as much 
lime in the dry substance wJien grown on the limestone as wlien 
grown on the sandstone. These results are not conclusive in con- 
nection with our work, iiowever, as the plants were grown on pow- 
dered rock without any addition of fertUizera. Thus the growth of the 
plants was limited mainly by the ease with which the different rocks 
afforded tlie mineral nutrients, and aii}^ effect whicli the other cliar- 
acteristics of the rocks could have had upon the plant growth was 
probably obscured. The results, however, when compared witli the 
data in tlie following pages, where much smaller increases in lime 
were induced in the plants, suggest tlie idea that the presence of an 
abundance of nutrient salts probably decreases the percentage of 
lime in the asli of plants grown in calcareous soils. 

Studies of D. Meyer - and Lemmermann et al.^ give data showing 
the influence of the lime content of the soil upon the lime content 
of the plant. The plants were grown in pots with additions of 
nitrogen, potash, and phosphoric acid. 

Lemmermann et al. worked with six sods, five of wliich contained 
from O.OS percent to 0.85 per cent of CaO, while the sixth soil, evidently 
calcareous, contaiiied 9.25 per cent of CaO. Rye, barley, and oats, 
grown on the calcareous soil witli 9.25 per cent CaO, contained less 
lime in the dry substance than when grown on the sods with 0.53 
per cent and 0.S5 per cent of lime. There was no depression of 
growth on the calcareous soil as compared with the other soils. Clover 
grown on the calcareous sod contained the same amount of Ume as 
wlien grown on the soil with 0.53 per cent CaO. The growths on the 
different soils were about tlie same. Mustard grown on the calcareous 
sod contained the same amount of Ume as when grown on the sod 
with 0.85 per cent CaO, the growths made on the two sods being 
approximately equal. Vetch grown on the high-lime sod contained 
more lime than when grown on any of the other soils, although the 
growth varied but Uttle between the sods containing 0.53 per cent. 
0.85 per cent, and 9.25 per cent CaO. 

' Ilaselhofl, E., Landw. Vers. Stat., 70 (1909), p. 53. 

s Meyer, D., Landw. Jahrb., 39 (1910), Erganzungsb. 3, p. 254. 

» Lcmmermaim, O., et al., Landw. Jahrb., 40 (1911), No. 1-2, p. 173. 



12 

Meyer used six soils, five of wliich contained from 0.1 per cent to 
1.03 per cent of CaO, and the sixth, wluch must have been calcareous, 
contained 1 1 .62 per cent of hme. Oats and buckwheat both contained 
less lime in the dry substance when grown on the soil Avith 11.62 per 
cent hme than when grown on the soil with 1.03 per cent of hme, 
although the growth was shghth' greater on the calcareous soU. The 
results with oats, therefore, confirm tliose obtained b}' Lemmermann 
with tliis crop. 

As far as can be generahzed from these results, it seems that on 
strongly calcareous soils many, but not all, jdants contain more lime 
and less iron, jjotash, and silica than wlien gi-owu on noncalcareous 
soils. 

PLAN OF THE INVESTIGATION. 

In brief, the plan of the following investigation was to grow several 
species of plants m adjacent field plats that contaiaed vaiymg 
amounts of calcium carbonate, and then determine the ash composi- 
tion of the plants from the different plats. Each species of plant was 
grown m the plats six different times, and samples of each crop were 
kept for analysis. 

Suice the object of the investigation was to determine the effect of 
the carbonate of hme only on the growth and mineral composition 
of the plants, it was attemped m the following experiments to make 
this soil constituent the variable factor affecting the growth. The 
plats were liberally and equally supplied with fertihzers to msiire the 
plants havmg sufllcient nitrogen, phosphoric acid, and potash avail- 
able for their maxinmm growth. When the ramfall was not sufficient 
the same quantity of water was added to each plat. In regard to 
sunhght, temperature, and humidity of the atmosphere, the plants 
ui any smgle experiment were, of course, exposed to identical 
conditions. 

It was not expected that the results obtahicd with these soils 
would be absolute for all calcareous soils. For mstance, the amount 
of organic matter in a sod, the water content, and the relative 
amount of sand and clay mflucnce to a certain extent the degree 
that carbonate of hme affects the growth, and probably the compo- 
sition of plants. But, as the variations in organic matter, etc., do 
not enthely obscure the effect of carbonate of hme on plants unless 
the amount of lime present is small, it was expected that the results 
with our sods would show in a general wa}'' the effect of carbonate of 
hme on the growth and composition of the plants tested. 

MATERIALS AND METHODS EMPLOYED. 

For the pm-pose of this investigation four plats 10 by 20 feet in 
area and 2 feet deep were employed, the first plat contauiing no car- 
bonate of Hme, the second approximately 5 per cent, the thhd 18 
per cent, and the foui-th 35 per cent. (PI. I.) 



ul. Id, Port.i R:co A~r. E 





Fig. 1.— Sweet Cassava Grown with wj Lime, Plat I. 



»-^ 


^ 




m 








^>^ 


■^ 


w«.i^ 




^■^^H 






■ 



FiQ. 2.~SwEET Cassava Ghown with 5 Per Cent Lime, Plat IL 



13 

The plats were prepared as follows : Holes of tl:e requii-ed size and 
depth were excavated in a clay soil, leaving a bank 3 feet wide be- 
tween each plat. These holes were filled with clay, sand, and dis- 
integrated hmestone in such proportions as to furnish soils of approx- 
imately equal texture and with the above percentages of calcium 
carbonate. Plat I was made up of approximately 33 per cent clay 
and 67 per cent sand; Plat II of 34 per cent clay, 60 per cent sand, 
and 6 per cent hmestone; Plat III of 33 per cent cla}-, 47 per cent 
sand, and 20 per cent hmestone; Plat IV of 32 per cent clay, 30 per 
cent sand, and 38 per cent hmestone. The soil in each plat was made 
uniform bj- long-contmued mixing. The texture of the soil m Plats 
I, II, and III was practically equal, that in Plat IV was somewhat 
heavier although good. As the iouT plats were surrounded bj- a 
ditcli, there was no drainage or wash from one plat to the other. 

The hmestone used was the finely dismtegrated material formed 
b}' the breakmg down of coraUme rock.' The acid analyses of the 
soils m the four plats are given in Table I\. 

Table I^'. — Anah/sis of (he soils of lliejhur plats. 



Insoluble matter 

Loss on ifrnition 

Ferric oxitUFe-O;,) 

Aluminiooxid (AI.O3) 

Liino(CaO) 

Ma^icsia (MgO) 

Potash (K.O) 

Phosphorus pentoxid (P.O5.) 

Total 

Nitrogen (N) 

Carbon dio-xid (CO2) 

Calcium carbonate (CaCOg). . 
Reaction to litmus 



11.97 
11.30 
1.03 



Flat II. Plat III. Plat IV. 



Per cent. 
69. 09 
10.97 
10.82 



Per cent. 
50. 7-1 
18.17 
9.26 
12.11 
10.90 
.79 
.15 



Wliile these soils were of good loamy texture, they were very low in 
organic matter, and were purposely kept so by remo\'ijig the roots of 
the various crops, since in the work previouslj- reported ^ there was 
evidence to show that in the presence of a large amount of organic 
matter the carbonate of lime would not exert its characteristic effect 
on the plants. Nitrogen, potash, and phosphoric acid were applied 
frec^uently and in such Ciuantities that the growth of plants was not 
checked by a lack of these elements in any of the plats. Water was 
also supphed when the rainfall was insufficient. In these plats the 
plants were grown under natural conditions of soil temperature, root 
space, and water supplj^, and the growths made were fuUy equal to 
those obtained under ordinary field conditions. 



1 Analysis and dcscriptiur 
! Porto Rico Sta. Bui. 11. 



of this material i 



I imder sample 216 in Porto Rico Sta. Bui. 11, p. 22. 



14 

Eight species of plants representing six families were tested in the 
plats, namely: Rice, soy beans, bush beans, rachshes, sunflowers, 
sweet cassava, sugar cane, and pineapples. Six different crops of 
each plant were grown at various times during the three yeai-s tliat 
the investigation was in progress, so the results represent the growth 
made under average weather conditions. It is beheved that the aver- 
age weights of the six crops represent withLa an accuracy of about 5 
per cent the comparative growths made on the different soils. 

Since the purpose of the investigation was to determine the effect 
of a soil constituent upon the ash composition of the plants, it was 
necessary to cut the plants before they reached complete maturity. 
If harvested at complete maturity, variations in the ash induced by 
the soil might liave been obscured by losses in the muieral constitu- 
ents which take place in the later stages of maturity.' Moreover, for 
our purpose the seeds or fruits from the plants on the different soils 
were not so important as the stems and leaves, since the ash compo- 
sition of the seeds is less affected by the composition of the soil than 
the vegetative portion of the plant. Wliile the mineral matter of 
the stems and leaves is assimilated from the soil, the mineral matter 
of seeds comes from a translocation of the mineral matter already in 
the vegetative parts of the plant.- 

Soy beans and bush beans were harvested in flower, wliile the 
leaves were still sound. Radishes were grown to the proper market- 
able size and not to seed. Sunflowers were gi-own until the heads 
had formed, but were cut before the seeds were filled, in order to 
secure unwithered leaves. Some of the rice was grown to maturity, 
while other crops were cut at a very early stage and when the panicles 
were just appearing. Tliis crop was analyzed at several stages of 
gi-owth. Sugar cane was grown for 148 days and sweet cassava for 
122 days. Pineapples were grown ten months. In preparmg the 
samples for analysis none but sound leaves were used, since the ash 
content of withered leaves is probably dependent more on the leach- 
ing to which they have been subjected than to influences of the soU. 

The methods used for the aiuxlysis of the plant ashes were essen- 
tially those of the Association of Official Agricultural Chemists. The 
ignition of the dry substance was carried out at a low temperature 
without the addition of calcium acetate, as the hme in the original 
substance could be determined more accurately without tliis addition. 
Comparative analyses made of the dry substance ignited with and 
\sdthout calcium acetate showed that in the absence of the acetate 

1 WiUarth, Romer, and Wimmer(Landw. Vers. Stat., 63 (1905), No. 1-2) have shown that considerable 
losses of potash and nitrogen oociir during the ripening of wheat and barley. Le C!erc and Brcazeale (U.S. 
Dep. Agr. Yearbook, lUO.S, p. 38'.i) have also shown that there is a loss of mmeral constituents, particularly 
at maturity, due to the leaching action of rain or dew. 

2 See Fittbogen, J., Landw. Vers. Stat., 6 (1864), p. 47-1; quoted by Dikow, A. von, Jour. Landw., 39 
(lS91),p. 134. 



15 

there was no volatilization of phosphoric acid at the temperature at 
wlucli the igtiitions were made. The separation of lime from iron 
and alumina was effected by precipitating the iron and aluminum 
phosphates in acetic acid .solution without addition of ferric chlorid, 
as tliis method possessed some advantages over the official method.' 
The iron was determined volumetrically with potassium perman- 
ganate. Aji aliquot was twice evaporated with sulphuric acid until 
fimies of sidphuric acid appeared. The diluted solution was then 
reduced mth iron-free zinc, filtered, and titrated with ^ or y^tj normal 
potassium permanganate. Tests with potassium tliiocyanate showed 
that between the final fdtration and titration with permanganate no 
ferric iron was formed. 

For the calculation of the results the sum of the constituents found 
in the acid solution of the ash was not taken as the amount of carbon- 
fi-ee ash, but the total ash was determined absolutely and the percent- 
ages of the various constituents calculated from tliis determination. 
The percentages of the constituents in the ash are tlius dependent 
upon the accuracy of the determination of the carbon-free ash, wliich 
is probably subject to an error of about one part in a hundred. The 
inorganic elements present in the dry matter of the plant were cal- 
culated by multiplying tlie percentages in the ash by the percentage 
of carbon-fi'ee ash and dividing by 100. In this process the percent- 
age of ash eliminates itself, so the percentages of the constituents 
found in the dry substance of the plant are more accurate, bcijig 
independent of the determination of carbon-free ash. 

GROWTH AND COMPOSITION OF VARIOUS PLANTS ON THE CAL- 
CAREOUS AND NONCALCAREOUS SOILS. 

The gi'owths of the various plants on the different soils and their 
ash compositions are detailed in the following pages. In all the 
tables Plat I refere to the check plat, containing no carbonate of 
lime, and Plats II, III, and IV refer to the plats containing, respec- 
tively, 5, 18, and .35 per cent of carbonate of lime. 

The results obtained with pineapples are reported in a former 
bulletm of this station. - 

BUSH BEANS. 

Six crops of bush beans, variety Improved Golden Wax, were 
grown at various seasons of the year. WMIe the growth made at 
different seasons varied greatly, plantings in March and April gi%ing 
the maximum growth, the relative growths made on the diS'erent 
plats appeared to be unaffected by the time of planting. The first 
crop of beans being grown to seed no data were secured on the weight 
of the plants, as when the seed were thoroughly mature the plants 

' A report on this method is given in Porto Rico Sta. Rpt. 1912, p. 21. 
'Porto Rico Sta. Bui. 11. 



16 



had shriveled and many leaves had dropped. Plat I yielded 127 
grams of shelled beans, Plat II 123 grams, and Plat IV 157 grams. 
Tlie five succeeding crops were harvested in flower, while the leaves 
were still green. Tlie absolute and relative growths made on the 
different plats are shown in Table V. 



Tab 


LE V. — Growth of bush beans on 


plats with different amoinits 


ofCaCO,. 






CaCOs 
in soil. 


Weight of green crops. 


Relative weights of crops from different 
plats (Plat I -100). 


Plat No. 


g 
K 
c 

C 


o 


'.C 

a 


S 
w 
p. 
o 


ft 

O 


1 
1 






Q 
ft 

o 




fcj 


Ota 

1 
> 


I 


P.ct. 

None. 
6 
18 
35 


Gmn. 
2,0S6 
1,913 
2,112 
2,855 


Gins. 
455 
510 
567 
660 


Gms. 
753 

1,035 
953 
954 


Gms. 
670 
740 
690 
615 


Gms. 
777 
776 
695 
637 


Gms. 
4,741 
4,974 
6,007 
5,721 


100 
92 
101 
137 


100 
112 
123 
145 


100 
138 
127 
127 


100 

no 

103 
92 


100 
100 
90 
82 




11 

HI 

IV. . . 


110±3 
109±5 
1I7±S 





It can be scon that the growth of the bush beans averaged, with 
allowance for the probable error, at least 5 per cent better on the 
soils Containing carbonate of lime. 

Crt)p B from the four plats was analyzed alone, crops D and F were 
analyzed together, using a composite sample made up of equal parts 
of the two crops. The whole plant above ground was used for 
analysis, stems, flowers, and leaves being fuiely ground up together. 
In Table \T arc given the percentages of the elements in the carbon- 
free ash and in the dry substance of the plants from the four plats. 

Table VI. — Analyses a/ bush beans from plats villi different amounts of CaCO^. 
CROP IS. 







-Analyses of carbon-free ash. 


Ash constituents in dry substance of plant. 






O 


2 








.a 




O 


:2 










Plat 


CaCOa 


^ 


^ 


C3 


O 


^ 


^ 


C3 


^ 


^ 


rt 


O 




._; 


£ 


No. 


in soil. 


o 
o 


S 


So 




9. 


O 


•1 


o 






.d 


9. 


O 






S 


n 




s 


^ 


■~ 


"£ 


fcl 


a 




o 












hJ 


a 




Ph 




m 


o 


►J 


s 


p.. 


Ph 


i^ 


m 


2; 




P.cl. 


P.cl. 


p.ct. 


P.ct. 


P.cl. 


p.cl. 


P.cl. 


p.cl. 


p.ct. 


p.cl. 


p.cl. 


p.ct. 


P.ct. 


P.ct. 


p.ct. 


I 


None. 


35. 54 


10.84 


S.14 


32.98 


1.54 


12.05 


10.62 


3.77 


1.15 


0.86 


3.50 


0.164 


1.28 


4.03 


n.... 


5 


29.95 


12.31 


7.39 


32. 3S 


1.44 


12.85 


11.48 


3.44 


1.41 


.85 


3.72 


.165 


1.48 


3.62 


ni. .. 


IS 


26.02 


11.15 


7.16 


31.82 


1.22 


10. 8C 


11.63 


3.03 


1.30 


.83 


3.70 


.142 


1.26 


3.58 


IV.... 


35 


2S.53 


10.03 


7.02 


34.45 


.99 


8. 03 


12.05 


3.44 


1.21 


.85 


4.15 


.119 


1.04 


3.76 



CROPS D AND P. 



I 


None. 


25.91 


7. 67 8. 27 


33.82 


1.28 


10.11 


11.20 


2.90 


0.86 


0.93 


3.79, 0.143 


1.13 


3.77 


11... 


5 


26.82 


7. 90 8. 36 


31.85 


.96 


10. m 


11.20 


3.O0 


.89 


.94 


3.571 .108 


1.13 


3.85 


III... 


IS 


28.12 


-.2" 8. .57 


36.82 


.8S 


8.97 


10.82 


3.04 


.79 


,94 


3.98 .095 


.97 


3.62 


IV.... 


35 


25.57 


6.30 7.94 35.19 


.82 


8.38 


11.73 


3.00 


.74 


.93 


4.13 .096 


.98 


3.76 



17 

While the content of ash, lime, phosphoric acid, potash, silica, and 
nitrogen was practically the same for the two sets of samples analyzed, 
the magnesia and iron content was liigher in crop B than in crops D 
and F, and it will be noticed that this difference holds for the plants 
gro\\ii on all four soils. These results are rather striking when it is 
considered that crop B and crops D and F were grown in different 
years and that no magnesium M^as added in any fertUizer. 

The extent to which the carbonate of hme in the soil influenced tlio 
ash composition and amount of inorganic substances in the dry matter 
of the plants is better shown in Table VII. Here the percentages of 
the different elements present in the plants grown in Plat I are ex- 
pressed as 100, <ind the percentages present in the plants grown in 
Plats II, III, and IV are expressed relative to 100. Table VII gives 
only the average result of the three crops analyzed. In calculating 
the average, twice the value was given to the analysis of the com- 
posite sample of crops D and F that was given to the analysis of crop 
B, so the average result gives an equal value to aU three crops, B, D, 
and F. 



Table VII. — Rclaliic nsh composition of bush bcans/rom different plats. 







Relative composition of ash (percent- 


Rcla 


ivo ash content of drv substance ( percenta5;es 




CaCOs 


ages in plants from Plat 1=100). 




m plants from Plat 1=100 




Plat 




O 


3 








jd 




O 


2 










No. 


in soil. 


o 


g. 


If 


O 
1 


q 


O 


f 


o 

Q 

a 




a— 


1 


1 




•^ 






►J 






^ 




m 


u 


3 


s 




" 


" 


rjj 


Z 




Per ct. 






























I 


None. 


100 


100 


100 


100 


100 


100 


100 


100 


100 


100 


lOO 


100 


100 


ion 


n.... 


6 


97 


107 


9.S 


95 


81 


102 


103 


99 


no 


100 


98 


85 


105 


98 


m... 


IS 


97 


9S 


99 


105 


72 


89 


101 


97 


99 


100 


105 


73 


90 


94 


IV.... 


35 


93 


86 


93 


104 


64 


79 


108 


99 


92 


100 


112 


69 


85 


98 



From Table VII it is apparent that tlic chief effect of the carbonate 
of lime in the soil upon the ash constituents m the dry substance of 
the bush beans or upon the composition of their ash lay m dimm- 
Lshmg the content of iron. The silica content is also considerably 
dimmished m the plants grown on the fourth plat. The content of 
lime, phosphoric acid, and nitrogen m the dry substance and in the 
ash is remarkably constant for the plants growii on all four plats. 
48882°^14 3 



18 

SOY BEANS. 

Six crops of Mammoth Yellow soy beans were grown. The plants 
were harvested in flower, while the leaves were still sound. The ab- 
solute and relative growths made on the four plats are given in 
Table VIII. 

Table VIII. — Growth of soy beans on plats with different amounts of CaCO^. 





CaCOj 
in soil. 


Green weight of crops. 


Relative weights of crops from difler- 
ent plats (Plat r=- 100). 


Plat 

No. 




P5g 
Q 




of 




^1 




1 


I 


o 
o 


d 

I 
o 


£ 


t 
o 




I 

n 

ni.... 
IV 


Per ct. 

None.. 
5 
18 
35 


Gvis. 
785 
605 
765 
675 


Gms. 
1,765 
1,678 
1,465 
1,671 


Gms. 
930 

788 
670 
730 


Gms. 
1,581 
1,592 
1,234 
1,612 


Gms. 
746 
662 

577 
815 


Gms. 
1,639 
1,520 
1,293 
1,675 


Gms. 
7,446 
6,845 
6,004 
7,178 


100 

97 
86 


100 
95 
83 
95 


100 
85 

72 
78 


100 
101 
78 
102 


100 
89 

109 


100 
93 
79 

102 


100 
90±2 
81±2 
95±3 



The average results show that the best growth of soy beans was 
made on the plat with no carbonate of lime; there was, allowing for 
the probable error, an 8 to 12 per cent decrease on Plat II, a 17 to 
21 per cent decrease on Plat III, and a 2 to 8 per cent decrease on 
Plat IV. 

Crops A, B, and C were analyzed together in a composite sample 
containing equal parts of the three crops, and crops D, E, and F 
were analyzed in another comj^osite sample. The results are shown 
in Table IX. 

Table IX. — Analyses of soy beans from plats with different amounts of CaCO^. 
CROPS A, B, AND C, 









Vnalys 


2S of ca 


rbon-free ash. 


A 


>li con 


tituejits in dry substance 


of plant. 






O 


2 








■s 




O 


2 










Plat 


CaCOa 


^ 




c3 


O 


.^ 


.-^ 




^ 


a 




O 


.-^ 


^ 


■z 


No. 


in soil. 


S 


'§d 


M 


q 


O 


1 


rt 


^^ 


So 


M 


O, 


o 








r 


1 


g 


.i 


1 


s 


1 


tti 

8 


1 


fe 


g 


1 






J 


a 




^ 


il 


m 


Q 


►^ 


s 




A< 




CO 


z 




P.ct. 


r.ci. 


p.ct. 


P.rt 


P.cl. 


P.cf. 


P.ct. 


P.cl. 


p.cl. 


p. cl. 


P.cl. 


P.cl. 


P.cl. 


P. ct. 


p.ct. 


I 


None. 


i3.91 


15.64 


10.10 


30. 55 


O.Sl 


7.40 


8.78 


2.10 


1.37 


0.89 


2. 68 


3.071 


0.65 


3.51 


II.... 


5 


23.23 


15. OS 


9.80 


27.45 


.78 


9.84 


9.05 


2.10 


1.36 


.89 


2.48 


.071 


.89 


3.65 


III... 


18 


26. 32 


14.76 


10.72 


28. 45 


.55 


8.21 


8.70 


2.29 


1.28 


.93 


2.48 


.048 


.71 


3.18 


IV.... 


35 


25. 47 


13.72 


9.59 


28. 70 


.58 


8.34 


9.11 


2.32 


1.25 


.87 


2.61 


.053 


.76 


3.28 



CROPS D, E, AND F. 



I 


None. 


20.57 


14. 01 9. 98 


34.63 


1.24 


6.32 


9.41 


1.94 


1.32 


0.94 


3.26 


0.117 


0.59 


4.17 


II.... 


5 


20.21 


13. 24 0. 53 


33.60 


.1.16 


7.19 


9.70 


1.96 


1.28 


.92 


3.26 


.113 


.70 


4.47 


III... 


18 


22.12 


12.87 11.83 


32.54 


1.09 


8.32 


9.58 


2.12 


1.23 


1.13 


3.12 


.104 


.80 


4.13 


IV.... 


35 


21.81 


12,02 10.35 


21.75 


.83 


6.47 


9.95 


2.17 


1.20 


1.03 


3.16 


.083 


.64 


4.13 



19 

The two samples, composed of three crops each, analyzed very 
nearly the same. The lime was a little higher and the potash and iron 
a little lower in crops A, B, and C than in crops D, E, and F. These 
differences hold for aU four plats, so they can hardly be chance 
variations. It seems probable that they arc due to cHmatic influ- 
ences which afl'ect the plant directly or through the soil. 

In Taljlc X are given the relative ash compositions and the relative 
amounts of ash constituents in the dry substance of the plants from 
the different plats, the percentages of the different elements in the 
plants from Plat I being taken as 100 in each case. The results ai-e 
an average of the two lots analyzed, given in Table IX. 

Table X. — Relative ash composition of soy heans from different plats. 







Relative composit 


on of ash (percent- 


Relat 


ve amounts ash constituents in the dry sub- 




CaCOa 


ages in plants from Plat 1=100). 


stanc 


(amounts present in plan 


sfromPlatI = 100). 


Plat 




O 


■s 


^ 










o 


^ 


^ 








No. 


in soil. 


o 


a 


io 




9. 


g 




o 


a 


'§d 




c 


o 


^ 






t 


a 


"S^ 


si 






1 


oT 


Si 


•fe^ 


1 


fc, 




S' 






a 


a 


g 




S 


1 


•£ 


g 


5 


i 






i, 




P.cl. 






























I 


None. 


11)0 


100 


100 


100 


100 


100 


100 


100 


100 


100 


100 


100 


100 


100 


II.... 


5 


98 


96 


96 


94 


9.5 


124 


103 


101 


98 


99 


97 


99 


128 


106 


Ill ... 


IS 


109 


93 


113 


94 


7S 


122 


101 


109 


93 


112 


95 


79 


123 


95 


IV.... 


35 


107 


S7 


100 


93 


70 


lOS 


105 


111 


91 


104 


97 


73 


113 


91) 



The carbonate of lime in the soil had little more effect in varying 
the ash content of soy beans than it had on bush beans. As with 
bush beans, the most notable variation appeared in the regular 
decrease in the iron content of the plant with mcreasing amounts of 
carbonate of lime in the soil. The other variations that occurred 
are of lesser order, not exceeding 10 per cent except in the case of 
silica. There was a small but regular increase in- the amount of lime 
in the dry substance of the plant with increasing amounts of lime in 
the soil; in Plat II, however, the increase was not greater than the 
probable error. Proportionate to the increase in lime, there was a 
decrease in the amount of magnesia in the dry substance of the plant 
with increasing amounts of carbonate of lime in the plats. The 
remaining constituents in the plants showed no parallehsm with the 
lime content of the soils. The gi-eater amount of silica in the plants 
grown in the calcareous soil appears anomalous. 



SUNFLOWERS. 



Six crops of large Russian sunflowers were grown. The plants 
were harvested when the heads had formed, but before the seeds were 
fully developed. At this stage the leaves were soimd, except a few 
of the lower ones, which were not included in the sample for analysis. 



20 



The al)solutc and relative growths made on the four plats are given 
in Tabic XI. The various parts of the plant were weighed sepa- 
rately, but as no one part appeared to be affected by the lime in the 
soil more than another, only the weight of the whole plant, except 
roots, is given in Table XT. 

Table XI. — Grov^lli of sunfluvcrs on pints vtlh diJJ'crmt i,mmmls of CaC'O^. 









C 


reen. 


eight of crops. 




Relative 


veights of crops from different 
plats (Platl=.100). 




■X 


3 






- 




w 














^ 


Plat 


Cat:Os 






























No. 


in soil. 


^ 


^ 






^ 
























'^ ^ 


ri^, 


"u 


n^ 




r-,a 


it 














M^ 






y 


H 




'^ 


W 


y 


*!^ 


a 


- 




W 


'^ 


u ^ 














n,7 


















® o* 






































































O 


o 


o 


o 


o 


o 






o 


o 


O 


^ 


" 


■^ 




]'. cl. 


Kgs. 


Kqs. 


Kgs. 


Kge. 


Kgs. 


JTi/s. 


Kgs. 
















I 


None. 


17.84 


22.51 


8.52 


10.80 


6.30 


5.56 


70.53 


Kill 


IIHI 


Kill 


KKI 


Kill 


Kill 


100 


II.... 


.■i 


14.45 


21.11 


9.06 


10.06 


6.28 


6.75 


68.61 


Ml 


94 


1116 


1111 


118 


V>.\ 


104±4 


III... 


18 


14. 08 


22.26 


6. SO 


9. fO 


4.79 


5.29 


62.62 


84 


99 


6H 


8,S 


90 


!15 


87±3 


IV.... 


35 


15. 38 


23. 02 


7.57 


7.80 


5.16 


5.33 


64.35 


86 


102 


S>J 


73 


97 


96 


91±3 



The averages of the relative growths show, with allowance for 
probable error, a possible increase of to 8 per cent in Plat II, a 
decrease of 10 to IG per cent in Plat III, and a decrease of G to 12 
per cent in Plat IV. The total green weights of the six crops give 
nearly the same results, except that in Plat II there is a slight decrease 
instead of an increase over Plat I. The average of the relative 
gi'owths is probably more accurate than the total weight of the six 
crops, since the former gives an equal value to each crop grown. 

Crop A was analyzed alone, and crops D, E, and F were analyzed 
together in a composite sample. In each case the leaves and stalks 
were analyzed separately. The results are given in Table XII. 

T.\ni.E XII. — Anali/sis of stinjlotrersfmm /ilalu milk rlijj'cirnt aiiioiiiU.i of CiiCO^ 
LE.\.VES— CROP A. 







.\nalyses of carbon-free ash. 


.\sh constituents in dry substance of plant. 






O 


2 








.c 




O 


2 










Plat 


CaCOs 


^ 


3 


ci 


O 


'-^ 


^ 


OJ 


^ 


a 


C3 


O 


.-V 


^ 


■A 


No. 


in soil. 


o 
o 


II 




q 


O 




o 


1 


M 


w 


q 


s 


























J 












a 


™ 






g 






a 


a 






■~ 








" 


H 


^ 


Ph 


" 


M 


o 


3 ■ 






Ph 


^ 


m 


^ 




P. et. 


p. ct. 


P.ct. 


P.cl. 


P.ct. 


p.ct. 


p.ct. 


p.ct. 


p.ct. 


P.ct. 


p.ct 


p.ct. 


P.ct. 


P.ct. 


P.ct. 


I 


None. 


33. 70 


11.39 


6.22 


24.92 


0.4-7 




15.47 


6.22 


1.76 


0.96 


3.86 


0.073 




4.48 


II 


5 


38. 06 


10.12 


5.54 


32.37 


.79 




17.49 


6.66 


1.77 


.97 


5.66 


.138 




4.97 


III. .. 


IS 


36. 93 


11.85 


5.54 


34.21 


.82 




14.62 


5.40 


1.73 


.81 


6.00 


.120 




3.98 




35 


































... 
















1 ' ' 









LEAVES— CROPS D, E, AND F. 



I 


None. 


25.92 


12.18 


7.02 30.19 


0.31 


7.32 14.70 


3.81 


1.79 


1.03 


4.44 0.046 


1.08 


3.78 


n... 


6 


29. 37 


11.71 


6.20' 31.24 


.3f 


8.79 16.38 


4. .81 


1.92 


1.02 


5. 12 . 062 


1.44 


3.51 


III... 


IS 


29.3' 


10. 95; 


6. 63 2S. 17 


.42 


8.72 15.74 


4.62 


1.72 


1.114 


4. 43 . 066 


1.37 


3.75 


IV.... 


35 


30. 30 


10.37' 


6.47 30.93 


.38 7.46 14.71 


4.46 


1.53 


.80 


4.55 .056 


1.10 


3.88 



21 



Table XII. — Analyses of suiiflowers from plats uilh different amounts of CaCO^ — Con. 
STALKS— CROP A. 





CaCOj 
in soil. 


Analyses of carbon-free ash . 


Ash constituents in dry substance of plant. 


Plat 
No. 


o 

o 

3 


O 
S 

a 

a 




q 


O 

s 


2 


3 


O 
o 

1 
3 


O 

a 

1 

1 
1 


od 
S 




O 

M 


2 


S 


I 

II.... 
III.... 
IV.... 


P.ct. 

None. 
5 

18 
35 


p.ct. 
14.74 
14.66 
15.03 
15.22 


p.ct. 
8.84 
8.27 
8.28 
8.07 


p.ct. 
7. OS 
7.25 
6.77 
6.83 


P.ct. 
49.06 
52.90 
50.86 
50.14 


p.ct. 
0.15 
.21 
.13 
.14 


p.ct. 




p.ct. 
10.36 
12.31 
11.28 
10.77 


p.d. 

1.53 
1.80 
1.70 
1.64 


p.ct. 
0.92 
1.02 
.93 

.87 


P.c(. 
0.80 

.89 
.76 
.74 


P.ct. 
5.08 
0.51 
5.74 
5.40 


P.cJ. 

0.016 
.026 
.016 
.015 


p.ct. 


P.c?. 
1.58 
1.74 
1.29 
1.33 



STALKS— CROPS D, E, AND F. 



None. 


13.11 


12.90 


6.25 48.60 


0.51 


1.68 10.31 


1.36 


1.34 


0.04 


5.01 


0.053 


0.17 


5 


10.94 


10.59 


4.82 


44.29 


.33 


1.4S 11.81 


1.29 


1.25 


.57 


5.23 


.039 


.17 


18 


11.34 


10. 8C 


6.71 


55.63 


.41 


1.90 10.22 


1.16 


1.10 


.69 


5.09 


.042 


.20 


35 


9.71 


8.60 


4.88 


50.51 


.34 


1.62 10.89 


1.00 


.94 


.63 


5.50 


.037 


.17 



The percentage of lime iii. the ash and in the dry substance of the 
plant was somewhat higher in crop A than in crops D, E, and F, 
in all four plats. The ash content was about 50 per cent higher in 
the leaves than m the stalks. There was about three times as much 
Imie in the leaves as in the stalks, twice as miich magnesia, about 
six times as much silica, and two and a half times as much nitrogen. 
The potash was some 20 per cent higher in the stalks than in the 
leaves. 

The relative ash compositions and relative amounts of asn con- 
stituents in the dry substance of the plants from the different plats 
are given m Table XIII, the percentages of the diiTerent elements 
in the plants from Plat I being taken as 100 in each case. In Table 
XIII the results are an average of crops A, D, E, and F. 

Tablk XIII. — Rclatiee ash composition of sunflowers from illjfrrnit plats. 
LEAVES. 







Relative composition of ash (percent- 


R elative amount a.sh constituents in dry substance 




raCOa 


ages in plants from Plat 1 = 100). 


(amounts present in plants from Plat 1=100). 


Plat 




O 


? 








.6 




O 


T3 

a 


^ 








No. 


in soil. 


o 


a 


.s~ 


W 


° 


d 


S 


o 

r1 


a 


id 




6 


d 


5 






a 


1 




1 




g 


-c 


a 


s 


p.-' 


jd 


t, 


S 


s 






































a 


a 


I^ 


Pm 


" 


m 


o 


►4 


a 




Ph 


" 


m 


J5 




P.ct. 






























I 


None. 


100 


100 


100 


100 


100 


lOO 


100 


100 


100 


100 


100 


100 


100 


loa 


II.... 


5 


113 


94 


88 


no 


134 


120 


u:'. 


127 


100 


100 


123 


149 


135 


98 


III... 


IS 


112 


94 


92 


104 


145 


119 


104 


117 


97 


97 


108 


148 


127 


97 


IV.... 


35 


117 


85 


78 


102 


123 


102 


100 


117 


85 


78 


102 


122 


102 


103 



I 


None. 


100 


100 


100 


100 


100 


100 


100 


100 


100 


100 


lor 


11... 


6 


87 


85 


81 


95 


84 


88 


110 


102 


98 


95 


III 


III... 


18 


90 


87 


102 


112 


82 


113 


102 


92 


87 


105 


111 


IV.... 


35 


81 


73 


81 


104 


74 


90 


106 


86 


76 


80 


M. 



The leaves from Plat II contained 27 per cent more lime, 23 per 
cent more potash, 49 per cent more iron, and 35 per cent more silica 
than the leaves from Plat I, and an equal amount of magnesia, 
phosphoric acid, and nitrogen. The leaves from Plat III tliffered from 
those of Plat I in containing 17 per cent more lime, 48 per cent more 
iron, 27 per cent more silica, and 8 per cent more potash; the leaves 
from Plat IV differed in containing 17 per cent more lime, 15 per cent 
less magnesia, 22 per cent less phosphoric acid, and 22 per cent more 
iron. 

The stalks from Plat II differed from those of Plat I only in con- 
taining 10 per cent more potash; the stalks from Plat III differed in 
contaming S per cent less lime, 13 per cent less magnesia, 14 per cent 
more potash, 15 per cent less iron, 18 per cent more silica, and 26 per 
cent less nitrogen; the stalks from Plat IV differed in containing 14 
per cent less lime, 24 per cent less magnesia, 14 per cent less phos- 
phoric acid, 9 per cent more potash, and 20 per cent less nitrogen. 

As the green weight of the stalks averaged twice the green weight 
of the leaves, it can be seen that the lime content of the combined 
leaves and stalks from Plat II was a little higher than that from Plat 
I, while the lime content of the leaves and stalks from Plats HI and 
IV varied little from the lime content of those from Plat I. The ash 
constituents of the combined leaves and stalks of Plat II differed 
from the ash constituents of the leaves and stalks of Plat I in contain- 
ing about 10 per cent more lime, 15 per cent more potash, 20 per cent 
more iron, and 15 per cent more silica; the combined leaves and stalks 
from Plat III differed in containing some 8 per cent less magnesia, 10 
per cent more potash, 20 per cent more iron, 20 per cent more silica, 
and 20 per cent less nitrogen; the leaves and stalks from Plat IV 
differed in containing about 20 per cent less magnesia, 17 per cent 
less phosphoric acid, and 13 per cent less nitrogen. 

RADISHES. 

Long Scarlet Short Top ratlishes were grown to the marketable 
size, which took about 30 days. Roots and tops were weighed 
separately, but as the proportion of root to top was unaffected by 
the different soils only the weights of the whole plants are given in 
Table XIV. 



23 

Table XIV. — Growth of radishes on plats trith different amounts of CaCO^ 





CaCOs 






Oreen. 


'eight of crops. 






Relative weight of crops from differ- 
ent plats (Plat •1=100). 


Plat 


a 


S 


n 


S 


M 


cs 


.'1^' 














°l^ 


No. 


insofl. 










^-'^ 


^-^.-^ 


















<;-g 


fQ " 


"s 


'^S 


w5 


^e 


t:< 


-=; 


cq 


d 





W 


fc. 


&< 
















ft.2 




a 


P. 


p, 




ft 










S '^ 


f^ft 


ua 


p.f^ 


op, 




z?! 








p 




H 








o 


O 


o 


o 


Q 


o 




o 


o 


u 


o 


u 


o 


<:o 




Per ct. 


Gms. 


Gms. 


Gms. 


Gms. 


Gms. 


Gms. 


Gms. 
















I 


None. 


1,037 


1,188 


1,637 


1,987 


1,344 


1,069 


8,252 


100 


100 


100 


100 


100 


100 


100 


n.... 


5 


1,112 


1,263 


1,234 


1,535 


1,288 


1,199 


7,631 


107 


106 


"h 


77 


96 


113 


96 ±5 


m... 


18 


1,012 


1,102 


1,472 


1,832 


1,211 


1,424 


8,053 


HS 


H(l 


9(1 


92 


90 


135 


100 ±5 


IV.... 


35 


1,123 


1,2S4 


1,4S4 


2,307 


1,581 


1,603 


9,322 


lOS 


106 


89 


116 


118 


151 


115±6 



The growth of radishes seems to be unaffected by the amount of 
CaC03 m these soils. Making allowance for the probable error, the 
growths on Plats I to III were equal and there was a 9 to 21 per cent 
increased growth on Plat IV. 

Crops A, B, and C were analyzed together in one composite samjjle 
and crops D, E, and F in another. Leaves and roots were analyzed 
separately. The results are shown in Table XV. 

Table XV. — Analyses of radishes from plats with different amotmts of CaCO^. 
LEAVES— CROPS A, B, AND C. 







Analyses of carbon-free ash. 


Ash constituents in dry substance of plant. 






O 


3 








J3 




O 


3 










Plat 


CaCOa 


^ 


s 


03 


O 


--. 


.-< 


a 




S 


;3 


o 


^ 


^ 


z 


No. 


in soil. 


o 

r1 


Id 


M 


q 


O 


* 


O 


id 


w 


q 


g 






.i 


1 


gc 


1 




i 


1 


§ 


i 
1 


r 


1 


fe 


.i 


S 










cu 


p. 




M 


o 


►q 






Ph 




m 


z 




P.ct. 


p.ct. 


p.ct. 


P.ct. 


P.ct. 


p.ct. 


P.ct. 


p.ct. 


p.ct. 


p.ct. 


p.ct. 


P ct 


P.ct. 


P.ct. 


P.ct. 


I 


None. 


21. 5C 


7.7C 


6.42 


22.76 


1.84 


7.45 


18.14 


3.90 


1.40 


1. 10 


4.13 


0.334 


1.35 


5.69 


n.... 


5 


23.79 


6.83 


6.23 


22.94 


1.46 


5.75 


17.80 


4.23 


1.22 


1.11 


4.08 


.260 


1.02 


5.63 


in.... 


IS 


24. OC 


6.38 


6.47 


25.37 


1.28 


6.39 


18.15 


4.36 


1.16 


1.17 


4.00 


.232 


1.16 


5.16 


IV.... 


35 


24.90 


6.96 


5.94 


32.16 


1.16 


3.79 


19.20 


4.78 


1.14 


1.14 


6.17 


.222 


.73 


5.00 



LEAVES— CROPS D, E, AND F. 



None. 23.28 


7.71 


6.60 


22.64 


1.07 


4.82 


17.68 4.12 


1.36 


1.17 


4.00 


0.189 


0.86 


5 2S.26 


7.11 


7.55 


21.61 


1.09 


4.66 


18. 16 5. 13 
19. 29 5. 22 


1.29 


1.37 


3.92 


.199 


.83 


18 27.07 


6.06 


6.24 


20.91 


1.19 


4.6C 


1.17 


1.20 


4.03 


.23C 


.87 


35 23.91 


5.62 


6.38 


25.29 


.67 


3.13 


19. 01 4. 55 


1.05 


1.31 


4.81 


.179 


.60 



5.20 
6.23 
6.35 
4.97 



ROOTS— CROPS A, B, AND C. 



4.12 


2.74 


6.12 53.39 


0.35 


0.44 


21.61 


0.89 


0.59 


1.32 


11.54 


0.076 


0.10 


h. U 


2.76 


6.5.3 49.72 


.33 


.711 


19.61 


1.01 


.54 


1.2.8 


9.75 


.006 


.14 


i.H\ 


2.52 


6.65 66.58 


.27 


.55 


19.83 


0.89 


.50 


1.32 


11.22 


.054 


.11 


4.30 


2.44 


6.06 67.67 


.30 


1.00 


20.09 


.86 


.49 


1.22 


11.59 


.060 


.20 



3.13 
3.22 
2.75 



ROOTS— CROPS D, E, AND F. 



I 


No 


ne 


5.24 


11... 




6 


6.77 


III. . . 




W 


5.38 


IV.... 




36 


6.10 



3.41 


6. 46 


61.02 


0.69 


1.16 


20.02 


3.39 


6. ,5(1 


61.51 


.33 


.82 


19.90 


2.90 


,'>.9f 


51. 9C 


.33 


.86 


20.88 


2.94 


6.03 


60.60 


.27 


.58 


21.55 



i.29 10.21 

I.29I 10.26 

1.25] 10.84 

1.30 10.90 



24 

The two series of composite samples analyzed veiy much ahke, 
although the variations between the two analyses from the same plat 
are greater, in many cases, than the variations between the analyses 
from any two plats m the same series. This is to be expected, as the 
six crops were not all grown at the same time. 

The effect of the carbonate of lime in the soil upon the ash compo- 
sition of the plant is shown in Table XVI, where all percentages are 
expressed relative to the percentages present in the plants from 
Plat I. The results in Table XVI are the average of the two analyses 
given in Table XV. 



Table XVI. — Relative ash<oinpos%lion of radishes from dijferent plats. 
LE.WES. 



Relative composition of ash (per- 
centages in plants from Plat 1=100). 



Relative amount ash constituents in dry substance 
(amounts present in plants from Plat 1 = 100). 



ROOTS. 


I 


None. 


100 


100 


100 


100 


100 


100 100 


100 


ino 


100 


100 


100 


100 


lOO 


11.... 


5 


118 


100 


104 


97 


75 


115 95 


112 


96 


99 


92 


71 


105 


105 


III... 


18 


106 


89 


101 


104 


67 


99 98 


104 


SH 


99 


102 


65 


94 


97 


IV.... 


35 


101 


88 


97 


104 


66 


139 101 


101 


US 


9V 


104 


64 


126 


lOO 



The amount of lime in the dry substance of the leaves increased 
about 20 per cent in Plats II, III, and IV. Sihca and iron in the dry 
substance of the leaves decreased irregularly from Plats I to IV, while 
the magnesia decreased regularly. In the dry substance of the roots 
there was an appreciable increase in lime in Plat II only; magnesia 
and iron decreased regularly from Plats I to IV. The amount of ash 
in the leaves increased shghtly from Plats I to IV. The composition 
of the ash in leaves and roots showed about the same variations as 
the ash constituents in the dry substance. 

Taking the plant as a whole Geaves and roots together), it appears 
that the plants grown on the plats with CaCOg differed from the check 
plants in containing about 12 per cent more lime, 7 to 17 per cent less 
magnesia, and 15 to 35 per cent less iron. 




FiQ. 1.— Sweet Cassava Grown with i -: i' 




FiQ. 2.— Sweet Cassava Grown with 35 Per Cent Lime, Plat IV. 



ul. It, Porto Rico Agr. E^pt, Station 






25 



SUGAR CANE. 



Sugar cane, variety Cristalina, was grown 148 days, which is about 
one-third of the time necessary for maturity. At the end of this 
period stallcs were forming but practically no leaves had withered. 
The figures in Table X\1I give the weights of the whole plants, loaves 
and stalks unseparated. 

Table X"\'II. — Growth of sugar cane on plats with different amounts of Ca<''0:^. 







Green weight of crops. 


Relative weights of crops from difler- 
ent plats (Plat 1 = 100). 




^ 


^ 


ID 


o 


o 


CD 


m 














.„ 


Plat 


CaCOs 


^-' 


^-^ 


■—' 


'~' 


^^ 


'~' 
















^ . 


No. 


in soil. 


■ 


^ 


■ 


^ 


W^ 


• 
















C-- 






<3 






o-S 


f^S 


s-< 




















§ 


!=! 


g 


■^ 


g 




"t. 


-^ 


B 


o 


Q 


W 


fe 


" 0- 














P.-S 


cS 


ag' 


a 


c 
















































































o 


o 


u 


o 




o 




o 


o 


o 




o 


o 


''• 




Per ct. 


Kgs. 


KV.«. 


RV». 


Kgs. 


Kgs. 


Kgs. 


Kgs. 
















T 


None. 


15.44 


6.06 


8.68 


8.96 


4.30 


6. SO 


50.24 


100 


10(1 


1(10 


10(1 


UIO 


10(1 


100 


n 


5 


13.30 


3. 48 


9.37 


9.93 


6.06 


5.44 


47.58 


S6 


.^7 


KIS 


111 


141 


X(l 


97±8 


ni 


18 


11.S.S 


4.23 


8.26 


7.09 


3.06 


4.42 


38.64 


7.=. 


7(1 


95 


79 


"1 


6.5 


76±3 


IV 


35 


10.58 


5.00 


6.58 


4.28 


6.00 


7.86 


40.30 


69 


83 


76 


48 


140 


116 


89±9 



On the average the growth of Plat II was practically equal to that 
on Plat I, but there was a decrease of 21 to 27 per cent on Plat III 
and a probable decrease on Plat IV of 2 to 20 per cent. 

Since the cane when cut had short, poorly defined stalks, only the 
leaves were used for analysis. Crop A was analyzed alone, and crops 
B, C, and D were analyzed together in a composite sample. The 
results are given below. 



Table XVIII.- 



■Analyses of sugar-cane leaves from plats with different amounts of 
CaCO,. 










Analyses of carbon-free ash. 


-Vsh constituents in dry substance 


of plant. 




O 


XI' 












o 


-a 










Plat 


CaCO, 




a 


a 


O 


^ 


^ 


S 


. 


a 


s 


O 


^ 


^ 


X 


No. 


in soil. 


O 
O 


'% 


1? 


M 


q 


O 


* 


O 


.a" 


So 

r 


M 


O 

i 


O 






^ 


1 


S^ 




a 


.§ 


.£ 


a 


1 


1 


a 


.1 


s 






►J 




Ph 


Pw 




m- 


O 


>j 




CU 


^ 


a 


CO 


z 




Per ct. 


P.ct. 


p.ct. 


p.ct. 


P.ct. 


P.ct. 


P.ct. 


P.ct. 


p.ct. 


p.ct. 


p.ct. 


P.ct. 


P.ct. 


P.ct. 


p.ct. 


I 


None, 


6.13 


3.90 


7.02 


23.78 


0.43 


56.02 


9.32 


0.48 


0.36 


0.65 


2.22 


D.040 


5.22 


1.46 


II 


5 


5.99 


3. 82 


6.60 


22. 92 


.36 


52.71 


9.33 


.56 


.36 


.63 


2.14 


.034 


4.92 


1.38 


III... 


IS 


5. .50 


4.03 


8.R7 


26.80 


.25 


53.75 


7.90 


.43 


.32 


.70 


2.12 


.019 


4.25 


1.22 


IV.... 


35 


5.36 


3.15 


6.94 


22.20 


.32 


53.67 


9.46 


.51 


.30 


.66 


2.10 


.030 


5. OS 


1..53 



CROPS B, C, AND D. 





None. 


7.10 


4.25 


7.04 


22.95 


0.36 


49.71 


7.86 


0.56 


0.33 


0.55 


1.80 


0.028 


3 91 


1 


6 


7.77 


4.41 


i'.91 


26.42 


.38 


47.27 


7.78 


.60 


.34 


.62 


2.06 


.030 


3 68 


11... 


18 


v. 97 


5.39 


8.S9 


26.86 


.58 


46.51 


7.36 


.59 


.40 


.65 


1.98 


.043 


3,35 


V....I 35 


6.7S 


.■5.72 


8.24 


21.71 


.39 


50.32 


8.10 


.55 


.46 


.S7 


1.78 


.032 


4.08 



1.34 
1.40 
1.40 
1.43 



26 

Crop A ran somewhat higher in sihca and total ash than the combined 
crops B, C, and D, otherwise there was Uttle difference between the 
two analyses in respect to the amount of ash constituents in the dry 
substance of the leaves. Considering the percentage composition of 
the ash, crop A ran higher in sihca, while tlie combined crops B, C, 
and D, were higher in hme and magnesia. 

The average relative composition of the leaves from the different 
plats is given in Table XIX. In calculating the average of the two 
analyses given in Table XVIII three times the value was given to 
analysis B, C, and D, that was given to analysis A, so Table XIX 
represents the average relative composition of four crops from the 
different plats. 



Table XIX.- 


-Relative ash compost 


io)l 


/sugar cat 


e lea, 


esfro 


Hi different 


plats 






CaCOs 


Relativecomposition of ash (percent- 
ages in plants from Plat I-IOOJ. 


Relative amounts ash constituents in dr^ 
stance (amounts present in plants from 
1 = 100). 


sub- 
Plat 


riat 




o 


5 








J3 




o 


S 










No. 


in soil. 


^ 


•s 




O 


-^ 


^ 


03 


^ 


S 


C3 


o 


^ 


^ 








o 
o 


a 


So 

r 


S 




o 


Xi 

S 


t 


1 


1°" 
•§.Ph 


i 


O 

S 
a 


o 








►J 


g 


t, 


Oh 


" 


Oi 




►4 


S 


Ch 


CL. 


" 


— 






Pit cl. 




























I 


None. 


100 


100 


100 


ino 


100 


100 


100 


100 


100 


100 


100 


100 


100 


100 


II.... 


5 


113 


101 


103 


106 


95 


95 


100 


112 


101 


102 


105 


95 


94 


100 


III. .. 


18 


110 


115 


126 


115 


110 


94 


90 


98 


105 


114 


102 


101 


S4 


94 


IV.... 


35 


100 


lOS 


lOS 


94 


91 


99 


103 


102 


111 


112 


97 


95 


101 


106 



The amount of the different ash constituents in the dry substance 
of the plant appears to be unaffected by the carbonate of lime in 
the soil; only in the plants from Plat II is there an increase in the 
amount of lime. The composition of the ash also appears to have 
been influenced very little by the character of the soil. In Plats 
II and III, but not in Plat IV, the percentage of Ume in the ash of 
the plants was increased by about 10 per cent. The ash of the 
plants from Plat III ran a little higher in all the elements except 
sihca. On the whole the carbonate of lime in the soil does not appear 
to have altered the ash composition of cane leaves in any regular way. 

SWEET CASSAVA. 

Sweet cassava, when harvested at the end of 122 days, was growing 
vigorously and had formed some fleshy roots. Six crops were grown 
at cUfferent seasons of different years. While the plants in Plat IV 
were never chlorotic, at times their leaves were noticealily lighter 
in color than those of the plants in Plats I and 11. (PI. II.) 

Koots, leaves, and stalks were weighed separately, but only the 
total weight of the crop is given in Ta]:)le XX, as the relative propor- 
tions of roots, stalks, and leaves did not vary with the different soils. 



27 

Table XX. — Growth of siveet cassava on plats xoith different amounts of CaCo^. 





CaCOa 
in SOU. 


Green weight of crops. 


Rel 


live weight of crops fr 


Dmdii 


fferent 










Plat No. 


S . 


£ 


2. 


S 


£ 


£ 


.sf^i' 












°^ 






■<s 


ns 


OS 


pa 


63 42 


f^3 


^" 


















N 


a 


N 




3 


^ 




a 


o 


H 


W 


t. 


a'^ 






oft 


s^ 


H-P. 


Sc. 




S-a 


3 o" 


P. 


o 


o 


a 


i^ 


0. 


















































-^ 


^ 






o 


o 


o 


o 






Prr ct. 


Eqs. 


Kos. 


.Eys. 


Kgs. 


K,». 


^^s. 


iTw. 
















I 


None. 


10.39 


12.98 


9.71 


S.22 


3.08 


6.13 


50.51 


10(1 


1(10 


10(1 


100 


10(1 


100 


100 


11 


5 


10.20 


12.93 


6.43 


6.95 


2.74 


5.98 


45.23 


9S 


10(1 


66 


85 


K9 


OS 


89 ±4 


UI 


18 


5.74 


11.50 


5.07 


4.60 


3.21 


5.36 


35.48 


hh 


89 


W. 


hii 


104 


87 


74±6 




35 


5.76 


7.28 


3.30 


2.72 


2.44 


4.77 


26.27 


OD 


56 


34 


33 


79 ' 78 


56±6 



The amount of growth made varied greatly with the seasonal con- 
ditions; crojDS E and F, which only made about half the growth of 
crops A to D, showed a corresponding smaller depression in Plats 
III and IV. (PL III.) From the average of the relative growths 
it appears that the growth of sweet cassava has been quite markedly 
depressed by the larger amounts of carbonate of lime and slightly 
depressed by the smaller amount. 

The analyses of the leaves, stalks, and roots of crops A, C, and F 
are given in Table XXI. 



Table XXI. — Analyses of sueet cassava from plats leilh different amoinits of CaCO^ 

LEAVE.S— CROP A. 







Analyses of carbon-free ash. 


Ash constituents in dry substance of plant. 






O 


2 








a 




O 


3 










Plat 


CaCOs 


^ 




Ol 


O 


..-N 


^ 


C3 


^ 


a 


C3 


o 


^ 


^ 


Z 


No. 


in soil. 


o 




id 


w 


q 


O 


i 


O 


'§o 


M 


O 


g 






a 


M 


&— 


1 




S 


1 


1 


ffi 




.a 
J3 




g 


2 






































hj 


a 


Ch 


&< 




m 


o 


fj 


a 


^ 


Ph 


^ 


CO 


!a 




Per ct. 


P.ct. 


p.ct. 


P.ct. 


P.cl. 


P.cl. 


P.ct. 


P.ct. 


P.ct. 


p.ct. 


P.ct 


p.cl. 


p.cl 


p.ct. 


p.ct 


I 


None. 


30.68 


10.10 


12.88 


30.33 


0.80 




8.37 


2.57 


0.85 


1.08 


2.54 


0.067 




4.14 


U ... 


5 


32.14 


10.79 


11. 4C 


30.67 


.93 


6.85 


8.79 


2.83 


.95 


i.(h: 


2.70 


.082 


O.60 


4.37 


ni . . . 


IS 


32.95 


11.67 


11.63 


26.36 


.82 


8.06 


9.12 


2.97 


1.06 


1.06 


2.40 


.075 


.74 


4.18 


rv ... 


35 


33.37 


11.16 


12. 51 


27.88 


.81 


7.98 


9.41 


3.14 


1.05 


1.18 


2.62 


.076 


.75 


4.37 



LEAVES— CROPS C AND F. 



I 


None. 


29.27 


6.66 


14.01 


30.60 


0.68 7.16 


9.22 


2.70 


0.61 


1.29 


2.82 


0.063 


0.66 


4.04 


11.... 


5 


29.92 


6.0J 


13.09 


27.16 


.49 7. CO 


9.02 


2.7C 


.54 


1.18 


2.45 


.044 


.63 


3.94 


in . . . 


IS 


31. 52 


6.5S 


14.22 


29.41 


. 46 6. 22 


9.46 


2.98 


.62 


1.35 


2.78 


.044 


.59 


4.08 


IV... 


35 


33.67 


6.-55 


13.89 


30.80 


. 46 6. 67 8. 44 


2.84 


..55 


1.17 


2.60 


.039 


.56 


3.93 



STALKS— CROP A. 



I 


None. 


25.02 


12.35 16.47 


36.13 


0.74 


0.87 


6.61 


1.65 


0.82 


1.09 2.39 


0.049 


0.06 


1.88 




5 


27.30 


11.14 16.83 


32.91 


.73 


1.06 


7.31 


2.O0 


.81 


1.23 2.41 


.053 


.OS 


1.66 




18 


26.98 


11.73 17.01 


35.73 


.73 


1.14 


8.12 


2.19 


.95 


1.38 2.90 


.059 


.09 


1.56 


IV... 


35 


27.10 


12.33 16.53 


34.01 


.63 


1.26 


8.53 


2.31 


1.05 


1. 41 2. 90 


.054 


.11 


1.52 



28 



Table XXI. — Analyses of sweet cassava from plats with different amounts of CaCOg- 
Continued. 

STALKS— CROPS C AND F. 







Analyses ot carbon-free ash. 


Ash constituents in dry substance of plant. 






O 


2 








fl 




O 


s 










ruit 


CaC03 


^ 






O 


r-.. 


^ 


03 


^ 


a 


rt 




'-^ 


.-N 




Nn. 


to soil. 


o 
o 

a 
3 


a 
1 


•go 


1 


o 


O 
1 


3 


1 

3 


.2 
1 

a 


■go 

Ph 


w 

1 


q 
1 


O 

3 
1 


2 




Per ct. 


P.ct. 


p.ct. 


P.cl. 


P.ct. 


p.ct. 


P.ct. 


P.cl. 


p.ct. 


p.ct. 


p. d. 


p.ct. 


P.ct. 


P.ct. 


P. a. 





None. 


23. Sb 


7.77 


16.56 


32.60 


0.65 


o.m 


7.93 


l.KS 


0.62 


1.31 


2.59 


0.062 


0.05 


1.23 


1 


5 


25.9'2 


6.7S 


19.91 


29.37 


.65 


1.17 


7.90 


2.05 


.5^ 


1.57 


2.32 


.051 


.OS 


1.35 


II 


18 


27.99 


7.06 


16.87 


29.17 


.66 


.93 


8.12 


2.27 


.57 


1.37 


2.37 


.05^ 


.08 


1.16 


V ... 


35 


29.00 


8.12 


19.47 


32.65 


.55 


.70 


7.83 


2.27 


.64 


1.52 


2.56 


.043 


.05 


1.14 



ROOTS— CROP A. 



I 


None. 


12.51 


8.82 


17.86 


45.28 


1.42 


1.85 


3.30 


0.41 


0.29 


0.59 


1.49 0.047 


0.06 


1.48 


II.... 


5 


15.00 


7.99 


15.91 


48.60 


1.04 


1.30 


3. 48 


.52 


.28 


.55 


1.69 .036 


.05 


1.49 


III... 


IS 


14.94 


8.44 


17.42 


47.99 


1.72 


1.56 


3.53 


.53 


.30 


.61 


1.69 .061 


.06 


1.06 


IV... 


35 


18.20 


8.89 


16.88 


42.04 


.97 


1.47 


3.65 


.65 


.32 


.60 


1. 49 . 034 


.06 


1.04 



ROOTS— CROPS C AND F. 



, 


None. 


16. 48 


7.84 


16.76 


35.86 


0.88 


1.80 


3.70 


0.61 


0.29 


0.62 


1.33 


0.033 


0.07 


0.78 


II.... 


5 


19.61 


7.60 


17.25 


33.55 


.86 


1.77 


4.14 


.81 


.31 


.71 


1.39 


.036 


.OV 


.74 


III... 


IS 


IS. 20 


7.85 


15.83 


33. 87 


.87 


2.06 


3.70 


.67 


.29 


.58 


1.25 


.032 


.08 


.73 


IV ... 


35 


21.00 


8.71 


15.89 


33.46 


.87 


3.45 


3.74 


.79 


.33 


.59 


1.25 


.033 


.13 





In the leaves aud stalks there is a great variation m the magnesia 
content of crops A and C and F. Tliis difference, which holds for 
all four plats, may be due either to different climatic conditions exist- 
mg at the time of growth, or to the crops being cut at different stages 
of growth, since this plant was grown for a certain nvmiber of days. 
With bush beans sunilar differences were obtamed between the mag- 
nesia content of crop B and the combined crops D and F. In this 
case the difference in the magnesia coiild not have been due to the 
crops being cut at different stages of development, since all the 
crops of bush beans were harvested in flower. 

The average relative compositions of the three crops from the dif- 
ferent plats are given in Table XXII. 



29 



Table XXII. — Relative ask composition, a/ s/ceet cassava from the different plots. 
LEAVES. 



Relative composition of ash (percent- 
ages in plants from Plat 1=100). 



STALKS. 


I 

II .... 
III.... 

IV.... 


None. 
5 
IS 
33 


100 
109 
113 
115 


100 
89 
93 

103 


100 
111 
103 
109 


100 
91 
94 
97 


100 
100 
101 

85 


100 
153 
13.8 
127 


100 
106 
113 
114 


100 
115 
126 
130 


100 
93 
104 
110 


100 
117 
116 
123 


100 
96 
107 
110 


100 
103 
112 
97 


lOO 
157 
155 
142 


10« 
99 
89 
87 


ROOT.S. 


I 

II .... 
III-.-. 
IV.... 


None. 
6 
IS 
35 


100 
120 
115 
136 


100 
94 
98 

106 


100 
96 
96 
95 


100 
101 
100 
94 


100 
86 
110 

84 


100 100 
84 109 
99 104 

136 105 


100 
130 
120 
145 


100 
102 
102 
112 


1(H) 
104 
99 
99 


100 
109 
104 
97 


100 
93 
114 

80 


100 
92 
107 
13,-) 


log 

S3 
80 



The amount of total ash in the loaves, stalks, and roots increased 
in all the lime plats by percentages varying between 2 and 14 per cent 
The amount of lime in the dry substance of the plant increased with 
the amount of lime in the soil in contradistinction to bush beans. 
Magnesia increased \vith the lime, although in smaller proportion. 
Phosphoric acid and potash remained practically constant in tliu 
plants from all the plats, but in the stalivs from Plats II and IV thero 
was an appreciable increase in the phosphoric acid. In the case of 
the leaves there seemed to be a tendency for the iron content to 
diminish mth the increase of carbonate of lime in the soil, but in tlie 
stalks and roots the iron content, though a little irregular, tended to 
be constant. For the plant as a whole, the iron content was little 
affected by the different soils, except for a small depression in tlie 
plants from Plat IV. The nitrogen content of the leaves was con- 
stant for aU four plats. The nitrogen contents of the stalks and 
roots from Plat II were the same as the check, while there was a 
depression in tlie nitrogen contents of the stalks and roots from 
Plats III and IV. 

UPL.VND RICE. 

Of the seven crops of rice grown, six were grown for periods ranging 
from 84 to 129 days and one for only 25 days. The crop grown for 



30 

25 days was not included in the average of relative growths. At 84 
days heads were just appearing, and at 129 days the heads were well 
filled out in the check plat. The data on the relative growths are 
given in Table XXIII. 





Table 


XXni.— Growth of 


rice, on plats with diff 


erent amounts of CaCO^. 






CaCO.i 
in soil. 


Green weight of crops. 


Relative weights of crops from dif- 
ferent plats (Plat 1=100). 


Plat 
No. 


CO 


If 


r5 


1? 

i2 ^ 


If 

o a£ 


^3 


If 


















1 






<^ 


«x 


O ^ 


qS. 


W §• 


■^ & 


r""g. 


4-s 

=0 ^ 


< 


«' 


d 





W 


&; 


6 


^^ 






ft'a 


R-^ 


p,-3 


a-o 


g.^ 


P.-0 


p.^ 


S- 


ft 


ft 


S" 


ft 


ft 


8- 


» 










































o-^ 


QM 


qS 


oS 






ON 








u 




u 




o 






Per ct. 


Gms. 


Gms. 


Gms 


Gms. 


Gms. 


Gms. 


Gms. 


Cms. 


















I 


None. 


2,690 


1,076 


96S 


2,190 


2,107 


2,439 


112 


11,470 


iik: 


IOC 


10( 


I0(i 


l(H! 


KHI 


KK] 


100 


n 




915 


573 


.•^49 


1,525 


1,581 


2,031 


51 


7,174 


34 


M 


57 


7(1 


75 


8.S 


46 


62±5 


HI.... 


18 


1,364 


249 


245 


254 


1,301 


1,306 


53 


4,719 


51 


23 


25 


12 


K-/ 


54 


47 


38±6 


IV.... 


35 


1,067 


279 


707 


1,269 


1,235 


1,481 


55 


6,038 


40 


26 


73 


58 


59 


61 


49 


53±5 



Tlie average of the relative growths sliows that there was a marked 
depression on all the calcareous soils, the growth on Plat III being 
only about a third of that made on the check plat. The plants in 
Plats II to IV were plainly chlorotic, the chlorosis generally appearing 
wlien the plants were about two or three weeks old. Some chlorotic 
plants in Plats II to IV died, while a few individuals recovered their 
green color and made almost normal growth. The majority of the 
plants, however, lived along in a more or less chlorotic condition, 
making very little growth. The surviving plants in Plats II to IV 
were somewhat beliind the plants in Plat I in flowering and maturing 
their seed. (PI. IV.) 

This somewhat unequal development of the plants at the end of 
any specified time made it advisable to analyze the plants at several 
stages of growth. In the analyses of the crops grown 102 and 129 
days only the green stalks and leaves were used, the withered leaves 
being discarded and the heads not analyzed for I'easons mentioned 
in the first part of this report. The crops grown 84 days had a few 
undeveloped heads, which were groinid up with the green straw in 
preparing the sample for analysis. The few leaves which wei-e with- 
ered at this stage were not incorporated in the sample. In analyzing 
the crop grown 25 days the whole plant, except the roots, was used, 
there being no dead leaves. This crop when cut had just commenced 
to show all the outward effects of the carbonate of lime, the plants 
being clilorotic and the growth depressed. The difference between 
the individual plants in the lime plats had not yet become apparent, 
however, the plants being pretty uniformly affected. The analyses 
of the various crops are given in Table XXIV. 



31 



Table XXIV. — Analyses of rice straw from plats with different amounts of CaCO^ 
CROP G (25 DAYS' GROWTH). 







Analyses of carl^on-free ash. 


Ash constituents in dry substance of plant. 






O 


!2 








4 




O 


2 










Plat 


CaC03 


^ 


a 




O 


'^ 


^ 


a 


^ 




^ 


O 


'-> 


^ 


z 


No. 


in soil. 


o 

-1 


So 


M 


q 


O 


i3 


O 




oO 


M 


o. 


O 






.1 

►J 


a 




1 


1 


i 
3 




3 


1 


.a 


iS 


1 


.1 
m 


ia 




Per ct. 


P.ct. 


p.ct. 


p.ct. 


p.ct. 


p.ct. 


P.ct. 


P.c/. 


P.c(. 


P.c/. 


P.rt. 


P.ct. 


P.c(. 


P.ct. 


P.c/. 


I 


None. 


3.22 


2.96 


6.14 


17.50 


2.76 


60.94 


22. 29 


0.72 


0.66 


1.37 


3.9C 


0.615 


13.58 




II 


5 


7.43 


4.04 


4.9f 


19.88 


2.11 


54.76 


17.69 


1.31 


.71 


.SS 


3.52 


.373 


9.69 




III.... 


IS 


6.0C 


3.42 


4.65 


20.40 


1.5S 


60.48 


17.74 


1.06 


.61 


.83 


3.62 


.280 


10.73 




IV.... 


35 


7.10 


3.05 


8.05 


16.40 


1.98 


52.72 


17.10 


1.21 


.52 


1.38 


2.80 


.339 


9.02 





CROP B (.84 DAYS' GROWTH). 



4.84 
5.82 
10.20 
12.04 



24.00, 0.31 

15.89| .34 

23. 46 . 27 

12. 70: . 18 



61.92 18.18 
57.31 19.13 
50.47| 16.61 



4.36 0.057 

3. 04 . 066 

3. 90 . 046 

2.14 .0.30 



11.26 
10.96 
8.38 
8.54 



1.87 
1.93 
1.99 
1.67 



CROPS C AND D (102 DAYS' GROWTH). 



14. 18 
13.44 
12.90 
13.36 



7.61 
6.72 
7.13' 



CROPS E AND F (1'29 DAYS' GROWTH). 



19.28 
24.03 
23. 20 
23.04 



1.54 
1.91 
1.83 
1.63 



It is probable that of all the analyses that of crop G, grown 25 days, 
gives the most accui-ate comparison of the effect of the carbonate of 
lime on the mineral nutrition of the plant. As already mentioned, 
the plants in the lime plats were somewhat slower m maturmg than 
those in the check. Accordmgly the analyses of the 84, 102, and 129 
day plants from the foiu- plats wotdd show variations in the ash com- 
position that were induced partly by the chemical character of the 
soil and partly by the stage of maturity. The analyses of crops B 
and F also tend to show the ash composition of tlie normal or average 
plant in Plat I and of the resistant individuals in Plats II to IV, for 
in tlie lime plats the greater portion of the sample was afforded by the 
few resistant individuals which grew weU; the plants which were 
most affected died and did not appear in the sample. Sample G, 
however, taken at 25 days, includes the less resistant plants and catches 
them all at practically the same stage of matiu'ity and yet at a time 
when their nutrition has been sufficiently disturbed to be manifest. 



32 

As the different crops were grown at various seasons of different 
years, as well as to different stages of maturity, one is hardly justified 
in comparing the different analyses to see how the ash composition 
of rice straw varies with its development. It appears, liowever, 
that there is a constant decrease in the percentage of iron as the plant 
approaches full maturity. 

The relative composition of the different crops from tlie four ])lats 
is shown in Table XXV. 

Table XXV. — lielative ash composition of rice straw from the different plats. 
CROP G (25 DAYS' GROWTH). 





CaCOa 
in sou. 


Relative composition of ash ( percent- 
ages in plants from Plat I- 100). 


Relative amounts ash constituents in dry sul)- 
stance (amounts present in plants from Plat 
1=100). 


PUit 
No. 


o 

.1 


O 
S 

1 
1 


1 . 

1 


O 


d 
1 


d 


i 


d 

.1 

►J 


d 

1 
1 


2 


d 
W 


d 
1 


d 

M 


g 
1 


I 

II 

HI.... 
IV.... 


Per a. 

None. 
5 
18 
35 


100 
231 
186 
220 


100 
136 
116 
103 


ino 
81 
76 

131 


100 
114 
117 
94 


100 

57 


100 
90 
99 

87 


100 
79 
80 
77 


100 
182 
147 
168 


100 
108 
92 
79 


100 
64 
61 

101 


100 
90 
93 


100 
61 
46 
55 


100 
71 
79 
66 





CROP B (84 DAYS' GROWTH). 



I 




100 


100 


100 


100 


100 


100 


100 


100 


100 


100 


100 


100 


100 


100 


11 


5 


107 


r20 


120 


66 


110 


93 


105 


113 


126 


1'26 


70 


114 


97 


103 


III.... 


18 


128 


122 


211 


98 


87 


82 


92 


116 


110 


192 


SO 


79 


74 


106 


IV.... 


35 


136 


111 


249 


53 


58 


82 


93 


125 


102 


231 


49 


53 


76 


83 



CROPS C AND D (102 DAYS' GROWTH). 



None. 


100 


100 


100 


100 


100 


100 


100 


100 


100 


100 


100 


100 


100 


5 


150 


123 


116 


123 


■ 124 


9(1 


95 


143 


118 


lU 


116 


117 


86 


18 


199 


148 


129 


132 


171 


83 


91 


181 


135 


118 


120 


154- 


76 


35 


171 


127 


116 


128 


176 


85 


94 


162 


122 


110 


120 


16V 


SO 



CROPS E AND F (129 DAYS' GROWTH). 



I 




100 


100 


100 


100 


100 


100 


100 


100 


100 


100 


100 


100 


100 


100 


II 


5 


120 


125 


75 


125 


110 


93 


88 


103 


109 


65 


109 


100 


81 


124 


III.... 


IS 


1,85 


116 




120 


120 


95 


76 


140 


89 


65 


92 


93 


73 


119 


IV.... 


35 


162 


112 


80 


119 


110 


96 


83 


133 


93 


66 


100 


93 


80 


106 



The youngest crop, G, seems to show more disturbance in its ash 
composition than the other crops. In tliis crop the most marked 
effect of the carbonate of lime upon the plant ash has been in greatly 
increasing the amount of lime and in diminishing the amount of iron, 
total ash, and silica. The same, although less marked, variations 
occur in crop B as in crop G. Crops C to F on the Ume plats also 
show in their ash composition a great increase in Ume and a diminu- 
tion in total ash and silica, but no diminution in iron. 



33 



The percentage of magnesia in the ash is higher in the plants from 
the lime plats than in the check plants in all the crops. The phos- 
phoric acid, potash, and nitrogen show great irregularitj^, the plants 
from the lime plats being sometimes much higher and sometimes much 
lower in these elements than the check plants. 

GENERAL SUMMARY OF EXPERIMENTAL RESULTS. 

THE EFFECT OF CARBONATE OF LIME OX THE <;Rf)WTH OF PLANTS. 

The average relative growths of all the plants on the four plats are 
shown in Table XXVI. 

Table XXVI. — Arcmr/r rrlatire ffroiiihs vinde nn tlif pints hy tlie diffcrnit plants. 
[1 irowtli made on Plat 1= lon.] 



CaCOsin 


Bush 


Soy 


Sun- 


Radishes. 


Sugar 


Sweet 


soil. 


beans. 


beans. 


flowers. 


cane. 


cassava. 


1 Per cent. 














' None. 


100 


100 


100 


100 


100 


100 


5 


100±3 


90±2 


104 ±4 


96±5 


97±8 


89±4 


18 


109±5 


Sl±2 


87±3 


100±5 


78±3 


74±6 


35 


117±8 


95±3 


91±3 


115±6 


89±9 


56±6 



62±5 
38±6 
o3±5 



^Vf tcr making allowance for the probable error of the average results, 
it appears that the growth of bush beans and radishes was certainly 
not depressed on- the calcareous soils, but possibly shghtly increased. 
Soy beans, sunflowei-s, and sugar cane were little affected in their 
growth by the calcareous soils of Plats II and IV, but on Plat III 
their growth was unmistakably diminished, the decreases being four 
to nine times the probable error. The growth of sweet cassava was 
sUghtly decreased on the moderately calcareous soil of Plat II (PI. 
II, fig. 2) and strongly decreased on the more limy soils of Plats III 
and 1\ (PI. III). The growth of rice was greatly depressed on aU 
the hme plats (PI. IV). In brief then, the tolerance of the plants 
for the different amomits of carbonate of hme was as follows : Bush 
beans and racHshes were unaffected even by 35 per cent of CaCOj; 
sunflowers, soy beans, and sugar cane wore somewhat affected by 18 
per cent of CaCOg ; sweet cassava was somewhat affected by 5 per 
cent of CaCOg and markedly by 35 per cent; rice and pineapples 
were greatly affected by 5, 18, and 35 per cent of CaCOj. 

Rice and pineapples were the only plants that became chlorotic 
on the calcareous soils, although the other plants whose growth was 
but httle affected were often a somewhat Ughter green on the lime 
plats than on the check. In the case of soy beans, sunflowere, sugar 
cane, and rice it -ftdll be noted that the greatest depression in growth 
occurred on Plat III, with 18 per cent of CaGOj rather than on Plat 
IV Avith 35 per cent of CaCOj. As mentioned on page 13. Plat IV, 



34 

althougli of good texture, was heavier than Plats I to III. This 
heavier physical condition may have influenced the action of the car- 
bonate of lime, or the lime and physical condition of the soil may have 
affected the plant growth independently and oppositely. It seems 
more probable, however, that the physical condition of the soil 
influences the effect of the carbonate of lime upon the plant. 

Hilgard observed that "the gi'eater the clay percentage in a soil 
the more lime carbonate it must contain in order to possess the 
advantages of a calcareous soil."' And m the course of certain other 
experiments with rice, not reported here, where rice was grown on 
calcareous soils, we observed that on the heavier calcareous soils the 
growth was not depressed so much as on tlie more sandy soils. 

THE EFFECT OF CARBONATE OF LIME ON THE ASH COMPOSITION OF 
PLANTS. 

The extent to which the carbonate of lime in the soil influenced the 
composition of the ash and the cjuantities of ash constituents in the 
dry substance of the various plants is shown in Tables VII, X, XIII, 
XVI, XIX, XXII, and XXV. 

In summarizing tlie effect of the carbonate of lime in the soil upon 
the ash composition of the plant, it is assumed that the differences 
in ash composition, which occur between the plants grown on the 
check and calcareous soils, have been induced by the soil. This 
assumption is justifiable in so far as other factors tending to induce 
variations in the asli, such as differences in climate and differences 
in maturity of the plant, have been ecjualized or eliminated. As 
pointed out in the previous pages, it is beUeved that in growing tlie 
plants and taking the samples these factors have. been ecjualized, 
except in the case of the samples of rice gi-own S4, 102, and 129 days. 
All the analyses of rice are given in Table XXV, but in the following 
summary only the analysis of the 25-day sample is considered, for 
the reason given on page 30. 

The carbonate of hme in the soil increased the jierceutage of lime 
in the ash of rice very markedly. The percentage of lime in the ash 
of sweet cassava from Plat IV was also markedly increased. Soy 
beans, sunflowers (combined leaves and stalks), and sugar cane, 
however, showed very slight increases in the lime of the ash. In 
the radish plants from the plat with 5 per cent of CaCOg there was a 
17 per cent increase of lime in the ash, while in the ashes of radish 
plants from plats with 18 per cent and 35 per cent of CaC03 there 
were progi-essively smaller increases of lime. This is analogous to 
the results of Lemmerman et al. and Meyer (see p. 11) with oats. 
The lime in the ash of bush beans slightly decreased rather than 
increased with increasing amounts of CaCOg in the soil. 

> Hilgard, E. Soils. New York and London, 1906, p. 369. 



35 

The magnesia content of the ash of rice was considerably increased, 
on the calcareous plats, although the increase was not comparable 
with that of lime. With sweet cassava :uid sugar cane the magnesia 
in the ash was little if at all affected. With radishes, sunflowers, and 
soy beans there was cjuite a marked depression in the magnesia con- 
tent of the ash of the plants from Plat IV and shgiit depressions in 
the ashes of plants from Plats II and III. Bush beans showed a 
depression in the magnesia in the ash in Plat IV only. 

The amount of phosphoric acid in the ash did not appear to be 
affected in any constant manner, in any of the plants tested, by the 
carbonate of lime in the soil. Variations occurred, but they were 
irregular, showing no correspondence with the lime content of the 
soils. 

The same tendency to constancy and Lick of eft'ect of the carbonate 
of lime is apparent in the figures for potash. 

In regard to the pei-centage of iron in the asii, bush beans, soy 
beans, radishes, and rice sliowed a marked and fauiy regidar decrease 
with increasing amounts of hme in the soil. The combined leaves, 
stalks, and roots of sweet cassava showed a marked decrease in the 
iron content of the ash in Plat IV only. With sugar cane and sim- 
flower there was a tendency to a constant percentage of iron. 

The percentages of silica are iiTegular, but on the whole they were 
little affected by the carbonate of lime. Wliere large variations 
occurred, the percentages of sihca in tne plant were very small. 

The amounts of nitrogen in the dry substance were fairly constant 
for all the plants, so it seems very probable that the lime had no eft'ect 
on the nitrogen. However, in the stalks of sunflowers from Plats III 
and IV, and in the roots and stalks of sweet cassava from Plats III 
and IV there were noticeable decreases in the nitrogen; but the 
leaves of both plants from these plats showed no decrease in the 
nitrogen. 

The amount of total ash in the dry substance was slightly increased 
in all the plants, except rice, by the calcareous soils. For the most 
part these increases were only three or four per cent, but they occurred 
with great regularity with bush beans, soy beans, sunflowers, radishes, 
sugar cane, sweet cassava, and pineapples,' cane leaves from Plat III 
being the only exception. It thus seems very probable that this is a 
general effect of carbonate of lime on aU these plants except rice. 

Practically the same observations as were made on the quantity of 
lime, magnesia, phosphoric acid, etc., in the ash, apply to the quanti- 
ties of these elements in the dry substance of the plant. There were 
some differences, however, between the relative ash compositions 
and the relative amounts of the ash constituents in the dry substance, 

1 See Porto Rico Sta. Bui. 11, p. 35. 



:',6 

due to the increase in totiil ash of the phxnts on the calcareous soils. 
For uistance, the amount ot lime in the di-y substance of sweet cassava 
(combined leaves, stalks, and roots) increased in Plats II, III, and 
IV, while the increase ot lime in the ash was marked in the plants 
from Plat IV only. There were also moderate increases in the 
amounts ot lime in the dry substance of sunflowers (combined leaves 
and stalks) and radishes (leaves and roots) on Plats II, III, and 
IV. But it should be noted that these increases were of smaller 
magnitude on the ])lats with 18 per cent and 35 per cent of CaCOg 
than on the plat with 5 per cent; in fact, on the plat with 35 per cent 
of CaC03 the combined leaA'es and stalks of simflowers contained 
little if any more lime than on the check plat. This would seem to 
point to sunflowers and radishes having a certain regulatoiy power in 
the absorption of lime from strongly calcareous soils. 

Wliat was true of the effect of tlie calcareous soils on the quan- 
tity of magnesia in the ash ol the plants holds also for the effect on 
the cjuantity of magnesia in tne dry substance with slight modi- 
fications. Bush beans and soy beans showed onl> slight decreases 
in the quantity of magnesia in the dry substance on Plat IV^. With 
sunflowers and radishes there were sUght decreases Li the magnesia 
on Plat III and marked decreases on Plat IV. vSugar cane and sweet 
cassava on all the calcaieous soils contained slightly more magnesia 
than on the check soil. 

The quantities of 2>otash and phosphoric acid in the dry substance 
of the plants did not seem at all affected by the carbonate of lime. 
As a whole, the results wei'e fairly constant and where variations 
did occur they were irregular, pointing to neither an increasmg nor 
de]iressing effect. 

With regard to the amount of silica iji the dry substance there was 
a marked and significant decease with rice only. 

The regular variations in asli composition and in quantity of the 
mineral constituents in the dry substance of tlie plants that were 
induced by the carbonate of lime are summarized below: 

Bush beans. Decrease in Fe^Oj in the ash and dry substance. 

Soy beans. Slight increase in CaO, slight increase in IMgO, and 
marked decrease in Fe203 in the ash and dry substance. 

Sunflowers (combined analyses of leaves and stalks). Decrease 
ui MgO and slight decrease in P.Oj in the ash. Sligiit decrease in 
MgO in the dry substance. 

Radishes (combined analyses of leaves and roots). Small increase 
in CaO, decrease in ilgO, and marked decrease in Fe;03 in the ash 
and dry substance. 

Sweet cassava (combined analyses of leaves, stalks, and roots). 
Increase in CaO, decrease in Fe203 (Plat IV only) in the ash. Increa?© 
in CaO, slight increase in MgO, slight decrease in Fe.jOg (Plat IV 



37 

oaly), 'IikI slight decrease in N (Plats III and IV only) in the dry 
substance. 

Rice. Large increase in CaO, smaller increase in MgO, and 
decrease in FcoOj m the ash. Decrease in total ash. Large increase 
in CaO, large decrease in FejOj and SiOj in the dry substance. 

Pixieapples.' Marked increase in CaO and marked decrease in 
MgO and Fe^Oj ill the ash. Large increase in total ash and large 
increase in CaO in the dry substance. 

Li general the carbonate of lime afl'ccted the ash composition of 
the plants m varying the quantities of lime, magnesia, and iron. 
All the plants, however, did not show variations in all three of these 
elements. In regard to the variations in the percentages of these 
constituents in the ash, the different jdants behaved as follows: 
Bush beans, iron alone decreased; soy beans and radishes, lime 
increased, magnesia and iron decreased; sunflowers, magnesia 
decreased; sweet cassava, lime increased: rice, lime and magnesia 
increased, iron decreased; ]nneapples, lime inci'eased, magnesia and 
iron decreased. In regard to the variations in the c[uantities of 
these elements in the dry substance of the plant, the results were as 
follows: Bush beans, decrease in iron; soy beans and radishes, increase 
in lime, decrease in magnesia aiid iron; sunflowers, decrease in 
magnesia; sweet cassava, increase in lime and magnesia, decrease 
in iron (in Piat IV only); rice, increase in lime, decrease in iron; 
pineapples, increase in lime. Thus the ])lants varied cpialitatively 
in regard to which mineral constituents were affected and quanti- 
tatively with respect to the degree that they were affected. 

THE EFFECT ON GROWTH COMPARED WITH THE EFFECT ON ASH 
COMPOSITION. 

In comparing the effect of the carbonate of lime on the growth 
of the plant with the effect on the ash composition of the plant, it can 
be seen that there was not always a parallelism between the two 
effects. For instance, the decrease in the iron content of bush beans 
on the calcareous soils was not accompanied by a. depression in 
growth; the slight increase in lime, the slight decrease in magnesia, 
and the marked decrease in iron in soy beans on the calcareous 
soils were accompanied by a slight depression in growth, although 
on Plat III where the growth was iiKjst de])ressed the changes in 
ash composition of the plant were less marked than on Plat IV where 
the growth was very slightly if at all depressed. The slight increase 
in lime, the decrease in magnesia, and the marked decrease in iron 
in radishes on the calcareous soils were not accompanied by any 
changes in the growth of the plant. The rather marked depression 



38 

in growth of sugar cane on Plat III can not be correlated watli any 
cbangcs m ash composition. 

Wliere, however, the growth was very markedly decreased and the 
plants showed an obvious intolerance for the calcareous soils, as 
observed with pineapples and rice, the marked decrease in growth 
was accompanied by marked changes m the ash composition of the 
plants. The increases in lime in the ash and dry substance of rice 
and pineapples on the calcareous soils were much greater than the 
increases in lime induced in the other plants whose growths were not 
so injuriously affected. The marked decreases in iron in the ash of 
rice and pineapples were not greater than the decreases in ii-on in 
some of the other plants whose growths were not depressed. Next 
to rice and pineapples the largest increase in lime occurred with sweet 
cassava in Plats III and IV, and on these plats the growth of the 
plants was markedly depressed. Bush beans, soy beans, sunflowers, 
radishes, and sugar cane, wliich showed either no decrease in growth 
or a smaller depression on the calcareous soils than rice, pineapples, 
and sweet cassava, showed either no increase or a smaller increase 
in lime in the plant than rice, pineapples, and sweet cassava. 

DISCUSSION OF BESULTS. 

The results reported seem to point to certain general facts. The 
individuaUty of the various plants with regard to the effect of carbon- 
ate of lime on theii" growth is very marked, some plants gro%ving 
equally well on the calcareous and noncalcareous soils and other 
plants doing veiy poorly on the calcareous soils. There is also an 
equal individuaUty of the plants in regard to the effect of carbonate 
of lime on theii' ash composition. This mdividuahty, shown experi- 
mentally, has an important bearing on the much discussed theories 
regarding the distribution of plants on calcareous and noncalcareous 
soils. 

Of the eight plants tested, oidy those plants wliich showed obvious 
injury and depression in growth from the carbonate of Ume showed 
a notable increase of Ume in the dry substance of the plant. Some 
plants, as bush beans, contained no more Ume in the dry substance 
when grown on the calcareous soil containuig 35 per cent of CaCOj 
than when grown on the soil that contained no CaCOj, and only 
1 per cent of CaO present as siUcate. It thus appears that providing 
there is a certain sufficiency of Ume in the soil it is useless to attempt 
to increase the Ume content of some plants by Uming.' 

It is also interesting to note that wliile the Ume content of pine- 
apples increased ^\^th the percentage of CaC'Oj in the sod, the Ume 
content of sunflowers was greatest on the soil with .5 per cent CaCOg 

1 Consideratile applications of soluble lime salts would probably increase the lime content of the plant 
oven when there is a sufficiency of lime in (he soil- 



39 

and progressively less on the soils with 18 per cent and 35 per cent 
of CaCOj, and the Hme content of bush beans was practically the same 
on all the soils. Thus with regard to the amount of Ume absorbed, 
pineapples behaved similar to vetch as observed by Lemmermann 
(see p. 11), sunflowers behaved similar to oats and buckwheat as 
observed by Meyer (see p. 12), and bush beans behaved similar to 
clover as observed by Lemmermann. 

The individual manner in which the different plants behaved with 
respect to their growth and ash composition on the calcareous soOs 
is doubtless due to individual dift'erences m the constitution and 
physiology of the roots. Suice Dyer ' found that the cell saps of 
various roots difi'ered in their acidity, difi'erences in the assimilative 
power of various plants for soil constituents have often been attributed 
to diflerences in the strength of the acids excreted by the roots of the 
various plants. But because the cell sap is acid it does not necessarily 
follow that the roots excrete an acid. Moreover, the only root 
excretion that has been well estabhshed is carbon dioxid. Therefore 
it does not seem justifiable to attribute the different behavior of the 
various plants on the calcareous soil to differences m the acid excre- 
tions of their roots. In the Hglit of recent investigations on the 
permeabihty of the membrane of plant cells it seems more probable 
that the differences observed were due to differences in the nature 
or reactions of the cell membrane. 

It appears that the diminished growth of some of the jilants on the 
calcareous soil is due to modifications induced in their ash composition 
by the carbonate of hme. This conclusion is based on two general 
assumptions, first, that ash analyses show differences in the mineral 
nutrition of plants, and, second, that the plants which have made the 
better growth have an ash composition more nearly approaching^ 
the optimum. Before detailing the modifications in ash composition 
that appear to have induced the injury in the plant, these two 
sources of doubt in the conclusion wiU be considered. 

In the first place, it should be remembered that an ash analysis 
does not give a moving picture of the ash composition of the plant 
during growth, but gives a picture of the ash composition at one 
stage of growth only. As the percentages of the elements in a plant 
vaiy considerably according to the stage of development of the plant, 
the complete picture of any one ash constituent would be repre- 
sented by a curve. But an ash analysis gives ordy one point on the 
curve, so we are really comi>ariug similar curves by points. The 
ash analyses show differences in the muieral nutrition of the plants 
if the points compared occupy the same relative position on the 
curves; that is, if the plants were analyzed at the same stage of 
maturity. As precautions were taken concerning the maturity of 

1 Dyer, B., Jour. Chem. Soc. (London), 65 (1894), p. US; BiedermannsCentbl. Agr. Chem., 23 (1894), p. 799. 



40 

the plants, the vahdity oi the conehision is ])ix)bably not affected by 
the firet assumption. 

The second assumption upon which the conchision is based, 
namely, that the plants which have made the better growth have an 
ash composition more nearly approacliing the optimum, is subject to 
considerable doubt because of our imcertainty concerning the factois 
and laws governing the ash composition of plants in general. A 
glance at a collection of ash analyses of the same plant shows that 
the same plant grown under different conditions may make practi- 
cally the same growth and yet have a very different ash composition. 
It does not necessarily follow, however, that under like conditions of 
growth the ash compositi(ju of a plant can be varied without affecting 
the growth. 

Some of the conditions afl'ectuig the ash composition of plants are 
known, and among these may be enumerated the following : The 
humidity, intensity of hght, temperature, and all those conditions 
which may be summarized as clunate, the water content of the soil,' 
the character of the soil,- the fertilizers applied,^ the stage of maturity 
of the plant,' and a great number of circumstances, such as the culti- 
vation of the soil, the thickness of tlie stands,^ and the time of plant- 
ing," wliich affect either the chmatic or soil conditions. All these 
factoi-s, of course, do not affect the ash composition independently, 
but more or less mterdepenilently, and therefore it is somewhat tliffi- 
cult to isolate and measure the effect of one factor. However, from 
the studies that have been made, it appeal's that climatic influences 
have the greatest eff'ect on the organic and inorganic composition of 
the plant.' 

It seems probable that for every set oi climatic conditions there is 
an optimum ash composition of the plant; and that when the ash 
composition is varied from this optimum, by varying the chemical 
character of the soU, the amount of nutrients available, etc., the 
growth is aff'ected. If this is so, variations in the ash composition 
of plants induced by differences in the character of the sod, under 
otherwise like conditions of growth, are significant. But variations 

' Fittbogen, J., Landw. Jahrb., 2 (1873), p. 353. Langer, L., and ToUens, B., Jour. Landw., 49 (1901), 
p. 209. Daszewski, A. von, and Tollens, B., Jour. Landw., 48 (1900), p. 223. Wilms, J., and Seelhorst, 
C. von, Jour. Landw., 46 (1898), p. 413. 

2 Hall, A. D., Jour. Soc. Arts |London], S2 (1904), p. 881; Jour. Agr. Sci. [England], 1 (190.5), No. 1, pp. 
65-S8. Stahl-Schroder, M., Jour. Landw., 52 (1904), p. 193. 

3 Kellner, O., et al., Landw. Vers. Stat., 39 (1891), p. 36L Dikow, A. von, Join. Landw., 39 (1891), p. 
134. Atterberg, A., Jour. Landw., 49 (1901), p. 97. 

* Tucker, G. M., and Tollens, B., Jour. Landw., 48 (1900), p. 39. HaielhoU, E., and Wemei, S., Landw. 
Jahrb., 44 (1913), No. 4, p. 651. Fliche, P., and Grandeau, L., Ann. Chim. et Phys., 5. ser.,8 (1876),p.4S6. 
Wilfarth, II., Romer, H., and Wimmer, G., Landw. Vers. Stat., (Vi (1905), No. 1-2. 

'Seelhorst, C. von, and Panaotovic, Jour. Landw., 47 (1899), p. 379. Atterberg, A., Jour. Landw., 49 
(1901 ), p. 97. 

' Stahl-Schroder, M., Jour. Landw., 62 (1904), p. 31. 

' Lawes, J. B., and Gilherf, J. II., Jour. Chem. S(x;. |I,ondon], 45 (1S84), p. 305. Stahl-Schriider, M., 
Jour. Landw., 52 (1904), p. 193. 



41 

in the ash composition of plants which are at different stages of 
maturity or grown imder iinhke chinatic conditions are vahieless as 
showing the effect of the cliaracter of the soil. 

But even under hke conditions of chmate, water supply, character 
of the soil, etc., the ash composition of plants can be varied m some 
directions without affecting the growth appreciably. This involves 
the question of "luxus consumption." From studies that have been 
made of the utihzation of nitrogen, phosphoric acid, and potash by 
the plant, it is apparent that when there is an excess of these nutrients 
present a plant may take up more of these elements than are neces- 
sary for growth.^ If, however, a certain greater amount of these 
elements is absorbed, the growth is depressed. Hence we may 
conclude that there is a minimum amount of an element required 
for a plant to make a maximum growth; that the plant can absorb 
luxus above this necessary amount without injury, but when the 
excess absorption exceeds a certain point injury to growth results. 

On this basis some changes in ash are significant while other's are 
not. The greater the change in any particular plant, however, the 
greater the probabihty that it is of consequence. The same order 
of change is probably not equally productive of effect on all plants, 
however, as some plants seem more sensitive to changes in their ash 
content than others. Nor is the same order of change necessarily 
significant for all the mineral elements.^ 

The question whether there ai-e certain ratios that shoidd exist 
between the elements in the ash, also has a bearing on what changes 
in the ash are significant. Wliile it is well proven that sodium can 
partially substitute potassium in the plant, it has not been established 
that there should be a definite ratio between these two bases.^ Ac- 
cording to some investigators, Ume and magnesia can substitute each 
other to a certain extent in the plant,* while others are more of the 
opinion that these elements should be present in a definite ratio. 
According to Champion and Pellet, the bases are more or less capable 
of mutual substitution but the sum of their chemical equivalents 
should be constant, each species of plant having a different constant." 

In short, it is reasonably sure that the differences in ash composi- 
tion of the plants grown on the calcareous soils were induced by the 
carbonate of hme and not by some climatic or accidental factor. But 
it is not certain that these differences in ash composition affected the 
growth, since we have no general knowledge as to what changes in 
ash composition are indicative of impaired nutrition. The most 

■ Jordan, W. H., New York State .Sta. Bui. 360, p. 76. 

* In the experiments of Dikow, Wilms, and Atterberg (loc. cit.), the P^O^ content of the plants showed 
less variation than the N and KjO content. 

3 Hartwell, B. L., and Pember, F. R., Rhode Island Sta. Rpt. 1908, p. 24;i. 

< Malaguli and Durocher, Ann. Sci. Nat. Bot., 4. ser., 9 (1858), p. 222. 

s Champion, P., and Pellet, H., Compt. Rend. Acad. Soi. [Paris], 80 (1875), p. 1588; Biedennanns Centbl . 
Agr. Chem., 8 (1875), p. 242; 9 (1876). p. 118. 



42 

that can be claimed is, that it is probable, whei-e marked alterations 
in ash composition accompanied diminished growth, that the changes 
in ash were the cause of the poor growth. For in adchtion to uncer- 
tainty as to what changes in ash composition are injuiious, there is 
the possibihty that differences in growth on the calcareous and non- 
calcareous soils are conditioned simply by the reaction of the soils, 
and that the soil reaction affects the plant in some other way than 
through inffuenciug the absorption of mineral nutrients. If this were 
so, the decreased growth might not be due to but accompanied by 
modiffcations in the ash. 

Thus, because of uncertainty concerning the laws governing the ash 
composition of plants there is considerable doubt of the accuracy of 
the conclusion that the diminished growth of the plants on the calca- 
reous soils is due to modifications in their ash composition induced 
by the carbonate of hme. With these general doubts in mind, how- 
ever, it appears that injury from the carbonate of hme, so far as it 
concerns the ash composition of the plant, may be due to one of the 
following modifications in the plant: 

1. An undue increase in the hme content of the plant or plant ash. 

2. A cUmunition in the iron content of the plant or plant ash. 

3. An increase in the hme combined with a decrease in the iron in 
the plant ash. 

Judging from the ash analyses reported here it seems that the first 
modification is the significant one, but judging from the results of 
direct experiments with pineapples the third modification appears 
more significant. Of course it is possible that the carbonate of hme 
may injure different plants differently, influencing the ash ccmposi- 
tion of one plant in one way and another species in another way. 

With respect to the assimilation of nitrogen, phosphoric acid, and 
potash it is evident that the carbonate of hme had no depressing 
effect. Even m the case of rice and pineapples, where the carbonate 
of hme i^lainly caused a nutritional disturbance, the plants grown on 
tlio hmy soils oftei^ showed liigher percentages of nitrogen, phosphoric 
acid, and potash than the check plants. These results are plainly 
contradictoiy of a view wluch has considerable acceptance, namely, 
that the nutritional disturbances of some plants on calcareous soils are 
due to a diminished potash content. The fact that fertilization with 
potash is not a specific for such disturbances also mihtates against 
this view. Of course, the results reported do not show whether the 
carbonate of hme had any effect on the economical utilization of nitro- 
gen, phosphoric acid, and potash, as those were appUed abundantly 
and in available forms. 



43 

The results for the phosphoric acid in the ash analyses would seem 
to contradict the theory of Crochetelle/ that the carbonate of Ume 
injures the plant by decreasing the assimilation of phosphoric acid. 
The experimeiits of Priainshnikow ^ with different phosphates also 
contradict Crochetelle's assumption, as the availabihty of phosphoric 
acid in mono and dicalcium phosphate, Thomas slag, and iron and 
aluminimi phosphates was not depressed by carbonate of hme, 
although the availabihty of phosphoric acid in bone meal and trical- 
cium phosphate was depressed. 

When the results reported here are compared with the results 
obtained by Fhche and Grandeau with certain trees,' strildng simi- 
larity in some respects is apparent. The bean tree, which was imaf- 
fected in growth by the carbonate of hme, was unaffected in its ash 
com230sition except for a depression in the magnesia. Tlie maritime 
pine and chestnut, whose gi-owths were strongly depressed on the 
calcareous soils, showed a marked increase in hme and a marked de- 
crease in iron and potash in the ash, when grown on the calcareous 
soils. All these trees contained a greater percentage of ash in the 
dry matter when grown on the calcareous soUs than wh6n grown on 
the noncalcareous soil. The above results differ from those obtained 
by us in that a strong depression of potash was noted in the pine and 
chestnut on the calcareous soils. 

The view that the injury to plants grown on calcareous soils does 
not he simply in increasing the hme in the plant seems to bo borne 
out by the chrect experiments with pmeapples and by experiments in 
progress with rice. It is also the conclusion arrived at by Fhche and 
Grandeau, and the opinion of Euler that " * * * ^j^j. gchafj. 
Uche Einfluss des Kalkbodens ein in chemischer Hinsicht indirekter 
ist."* Jost^ is of a similar opinion. Euler and Jost, however, 
beheve that the indirect action of the lime m injuring the plants hes 
in depressing the absorption of potash, apparently basmg their 
opinion on the analyses of Fhche and Grandeau. From the results 
reported here it appears that the incUrect action of the hme hes more 
in affecting the iron absorption than in depressing the potash; since 
when potash fertihzers are hberally used there is a depression in 
growth, but no depression in the amount of potash absorbed. 

It should be borne in mind that the results reported here do not 
warrant a decisive conclusion that the diminished growth of all those 

' Crochetelle, J., Ann. Sci. Agron., 2. ser., 8 (1902-.3), II, p. 43. 

> Prianishnikow, D., Landw. Vers. Stat., 75 (1911), Nos. 5-6, p. 357. 

' See p. 8. 

* Euler, II. Grundlagan und Ergebnisse der Pflanzcnchemie. Braunschweig, 1909, pt. 3, p. 153. 

6 Jost, L. Vorlesungen iiber Pflanzenphysiologie. Jena, 1908, 2. ed., p. 111. 



44 

plants which are aflFected by the carbonate of hme is due to the same 
change in ash composition. In fact, some quite marked changes in 
ash composition, as the decrease of iron in bush beans, occur without 
affectmg the growth. Aird some depressions in growth occur, as 
sugar cane on Plat III, with practically no change in ash composition. 
But those plants wliich showed the greatest injury from the calcareous 
soils, pineapples and rice, showed the most marked changes in their 
ash. The significant changes in the ash composition of these plants 
were apparently the increase in Ume and decrease in iron. 

StTMMABY. 

The residts show, in a soil well suppUed with nitrogen, phosphoric 
acid, and potash, the effect of 5, 18, and 35 per cent of carbonate of 
lime upon the growth and ash composition of bush beans, soy beans, 
sunflowers, radishes, sugar cane, sweet cassava, rice, and pineapples. 

The growths of bush beans and radishes were unaffected even by 
35 per cent of CaCOj. The growths of smiflowers, soy beans, and 
sugar cane, were somewhat depressed by IS per cent of CaCOj; the 
growth of sweet cassava was somewhat depressed by 5 per cent of 
CaCOg and markedly by 35 per cent of CaCOg; the growths of rice and 
pineapples were markedly depressed -vvith the appearance of chlorosis, 
by 5, 18, and 35 per cent of CaCOg. 

The carbonate of hme apparently had no effect on the amount of 
nitrogen, potash, and phosphoric acid contained in the various plants, 
but did increase shghtly the total carbon-free ash in aU the plants 
except rice, and modified either the amount of Hme, magnesia, or iron 
in the ash of all the plants. 

On the calcareous soils the Ume in the ash of bush beans was not 
increased, but there was a shgiit increase in the amount of hme in the 
ash of soy beans, sunflowers, and sugar cane. On the plat with 5 per 
cent of carbonate of hme, the hme in the ash of rachshes was increased 
about 17 per cent, but on the plats with IS and 35 per cent of carbon- 
ate of hme the increases of hme in tlie ash of this plant were progres- 
sively less. On the plat with 35 per cent of carbonate of Ume the 
amount of Ume in the ash and dry substance of sweet cassava was 
markedly increased. On all the calcareous soils the amount of Ume 
in the ash and dry substance of rice and pineapples was greatly 
increased. 

Some plants whose growth was little affected by the carbonate of 
lime (bush beans, soy beans, radishes, and sunflowers) showed marked 
decreases in the amount of iron or noticeable decreases in the amount 
of magnesia in the ash, when grown on the calcareous soils. 

The plants whose growths were most depressed on tlie calcareous 
soils (rice and pineapples) showed the greatest increases in the amount 



45 

of limo in the ash and dry substance of the plant, and also a marked 
decrease in the amount of iron in the ash. 

If the plants which have made the best growth have an ash compo- 
sition nearest the optimum, it would appear from these results as 
though the diminished growth of the plants most affected on the 
calcareous soils were due either to (1) an undue increase in the lime 
content of the plant or plant ash, or (2) an increase in the lime 
combined with a decrease in the iron in the plant. 

From these results alone it would appear as though the first suppo- 
sition were correct, but from direct experiments with pineapples the 
second supposition appears more probable. 



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